Medical

PHARMACOLOGY Administration of Medications General Information A. The scientific age has introduced an increasing number of pharmaceuticals appropriate for the relief of stress symptoms, for support of defense systems, and as adjuncts to other supplemental and curative therapies B. Drug nomenclature 1. Official name (generic, nonproprietary): designated title under which a drug is listed in official publications 2. Chemical name: descriptive name identifying chemical composition and placement of atoms 3. Trade name (brand, proprietary): manufacturer’s registered and legally owned name for a drug C. Sources of drugs 1. Active constituents of plants: for example, alkaloids, glycosides, gums, resins, tannins, waxes, volatile or fixed oils 2. Animal sources of biologic products: for example, enzymes, serum vaccines, antitoxins, toxoids, hormones 3. Mineral sources: for example, iron, iodine, Epsom salt 4. Chemically and biologically engineered substances: for example, human insulin D. Types of pharmaceutical preparations 1. Prepared by manufacturer in units for convenience of administration 2. Forms used include capsules, extended-release capsules, tablets (enteric coated, extended release), troches, pills, suppositories, powders, ampules, vials, delayed-release (repository) suspensions, prefilled cartridges, liniments, lotions, cream, ointments, pastes, aerosols, transdermal preparations 3. Chemical preparations: solutions (waters, true solutions, syrups), aqueous suspensions (mixtures, emulsions, magmas, gels), spirits, elixirs, tinctures, fluid extracts, extracts Basic concepts A. The administration of medications is a dependent function requiring a legally written order and knowledge of the medication’s cause and effect B. Legally, morally, and ethically, independent judgment is required before prescribed medications are administered C. Certain chemical agents alter, inactive, or potentiate other medications when mixed either before or after administration. D. Medications may be given for local or systemic effects. E. Pharmacologic actions of drugs tend to stimulate or depress physiologic activity. F. Medications may be given in a variety of ways, depending on factors such as the effect desired, rapidity of action desired, or the effect of the chemical on the tissues. Historical perspectives 1. Gums are mucilaginous secretions with the ability to attract and hold water. They are usually polysaccharides 2. Traditionally, drugs from animal sources include insulins some vitamins, and biologic agents (e.g., vaccines, immune serums). Antibiotics and pituitary hormones are also derived from animal sources 3. The advantage of genetically engineered drugs is their purity. Because no foreign proteins are involved, they do not induce antibody production. 4. An advantage of synthetic drugs is that they are pure chemicals and are unaffected by pharmacodynamic changes, mainly, deterioration in potency and stability. Another advantage of synthetic agents is their economy 5. A drug’s chemical name precisely describes the drugs atomic and molecular structure using exact chemical nomenclature and terminology. The chemical name is useful to chemists and biochemists. 6. The trade name, also known as the brand or proprietary name, is given to a drug by its manufacturer. Trade names are protected by trademark. 7. Each drug has only one generic or nonproprietary name. They are easily recognizable because the first letter of the name is usually not capitalized. 8. The PDR is written by the pharmaceutical company that manufactures the drug. It is commonly consultant in clinical settings Nursing management in drug therapy • Pharmacokinetics refers to the changes that occur to the drug when it is inside the body. • Pharmacodynamics refers to the effects of the drug on the body • Pharmacotherapeutics refers to the desired effects of the drug on the body • Adverse effects refer to other, unintended and usually undesired effects that may occur with drugs. • Contraindication and precautions refers to when the drug should not be used or must be used carefully with monitoring • A prototype drug is typical of a group of drugs within a drug class. • A clinical pathway is an interdisciplinary approach to care that establishes common protocols for patients with the same medical diagnosis. The pathway takes into account the drugs usually ordered as a treatment for or in response to a specific condition Safeguards in Drug Development and delivery The FFDCA of 1938 established the FDA as the agency for monitoring and controlling drug manufacture and marketing. The law allows the FDA to prohibit the marketing of any drug judged to be incompletely tested or dangerous. Once a new drug is developed, pharmaceutical manufacturers must establish the drug’s pharmacologic activity, safety, and toxicity. Thereafter, the drug can be tested for it effects in humans. There are four phases of clinical trials. Phase I to Phase III take place before a new drug is marketed. Phase IV, post marketing surveillance, takes place after marketing begins. Drug Preparation and Administration • The enteral route uses the GI tract for the ingestion and absorption of drugs. The enteral route also includes drugs that are administered through a nasogastric (NG) or gastrostomy (G) tube • Drugs given for a systemic effect by any route must be capable of being transported into the blood and distributed through the body to a location distant from the administration site. Certain drugs given topically are absorbed by the skin and distributed through the body systems to produce a systemic effect. • The parenteral route avoids or circumvents the GI tract and is associated with all forms of injection, less commonly used parental routes are intradermal (into the dermis), intra-articular (into a joint), and into the cerebrospinal fluid (intrathecal) • A common coating, the enteric coating, consists of a wax like layer over a tablet. Enteric coatings may be used to protect acid-labile drugs, to provide a sustained-release dose, or to guard against local adverse effects from a drug • Enteric coating resists the acid environment of the stomach but dissolves in areas where the local pH is neutral or slightly alkaline, as in the small intestine. The enteric coating consists of a wax like layer over the tablet. • Drug administered topically is applied to the skin or mucus membranes, including those of the eyes, ears, nose, vagina, rectum, and lungs. Most drugs applied topically to the skin or mucous membranes exert their effect at the site, which is a local effect • The intravenous technique administers a drug directly into the blood stream. An advantage of the intravenous route is that it allows administration of a large volume of drug • Subcutaneous drugs are administered under the skin into fat and connective tissue. These drugs must be highly soluble, low volume (less than 2 ml in a good-sized adult) and nonirritating to prevent tissue damage, tissue necrosis, and abscess formation CORE DRUG KNOWLEDGE Pharmacotherapeutics, Pharmacokinetics and Pharmacodynamics 1. Drugs entering the body by the enteral route first go through the portal circulation to the liver before they are presented to the general circulation. This is known as the first-pass effect or phenomenon, a metabolic process that usually involves extensive drug breakdown. 2. Typically, a drug already in solution will be absorbed faster than the same drug in a solid form. Similarly, a drug in suspension needs to dissolve before it can be absorbed, and a drug in true solution will be absorbed most rapidly. 3. The ratio of effective dose to lethal dose is called the therapeutic index. A wide therapeutic index means the drug is relatively safe. 4. Drug tolerance occurs when a fixed dose of a drug can no longer produce its effects or when successively larger doses of a drug are required to maintain the same level of effect. Tolerance is a significant issue in pain control. 5. An agonist is a drug capable of combining with receptors to initiate a drug action. Agonist drugs work directly to alter the biologic functional properties of the receptor to which they bind. Adverse effects and drug interactions 1. Anaphylaxis is a systemic reaction caused by contraction of smooth muscles and increased vascular permeability. Anaphylaxis is the most serious of allergic reactions. 2. A drug interaction occurs when one drug and a second drug or element, such as food have an effect on each other. This effect may increase or decrease the therapeutic effects of one or both of the drugs, create a new effect, or increase the incidence of an adverse effect. 3. Drugs accumulate in the body whenever the dosage exceeds the amount the body can eliminate through metabolism and excretion. A drug accumulation that causes problems is known as drug toxicity. 4. The liver is exposed first to relatively large concentrations of ingested drugs or other potential toxicants. 5. Drugs are eliminated unchanged, as metabolites, or in both ways. Most interactions involving drug excretion occur in the kidney but the liver and GI tract are occasionally sites of drug excretion interactions. 6. A synergistic effect occurs when two or more “unlike” drugs are used together to produce a combined effect. The outcome is a drug effect greater than any of the drugs’ activity alone. 7. An additive effect occurs when two or more “like” drugs are used together to produce an effect. The outcome is a drug effect that is the sum of each individual drug’s effects. 8. An antagonist drug interaction results in a therapeutic effect less than the effect of either drug alone. The second drug either diminishes or cancels the effects of the first drug. CORE PATIENT VARIABLES Life Span: Children Physiologic differences in children for example, the child’s immature body systems, greater fluid composition, and smaller size, affect core drug knowledge. The child’s small and immature body system makes over dosages potentially lethal. To determine pediatric dosage by body weight method, a ratio and proportion is identified. The usual dose per kilogram is ratioed to the unknown dose per the child’s weight in kilograms. The preferred injection site for infants and children up to 3years is the vastus lateralis. This muscle has few nerves and blood vessels and forms the largest muscle mass in this age group. In the neonate and infant, the scalp’s many superficial veins offer easy access. Life Span: Pregnant or Breast-Feeding Women Some drugs can cause teratogenic effects (i.e., physical defects) in the developing fetus Drugs that are lipophilic (fat soluble) easily pass through the placenta’s lipid membrane. Lipophobic, water soluble, and protein drugs do not pass easily across the placental barrier. Life Span: Older Adults Efficient renal function is a crucial factor in ensuring drug clearance from the blood, excretion from the body, and termination of drug action. Aging can significantly decrease renal efficiency by altering glomerular filtration and renal tubular secretion. So-called normal creatinine levels can be misleading and should not be interpreted as an indication of normal renal function in elderly patients. Despite the decline in the efficiency of glomerular filtration, serum creatinine levels often remain in the normal range because creatinine production declines with aging as muscle mass decrease, resulting in less overall creatinine to be filtered. COMMONLY USED TERMINOLOGY A. Chemotherapy: use of drugs to destroy invading organisms or abnormal tissue in the host B. Drug: chemical agent interacts with living systems and is employed to prevent, diagnose, or treat disease C. Drug legislation: laws that provide the standards for drug manufacture and distribution and protect the public against fraudulent claims about drug action (e.g., Federal Controlled Substances Act, regulations of the Federal Bureau of Narcotics and Dangerous Drugs, regulations by specific states) D. Drug standards: criteria for drug composition established by chemical or bioassay and published in official publications (e.g., United States Pharmacopoeia/National Formulary, Pharmacopoeia Internationalist) E. Pharmacodynamics: biochemical and physiologic effects of drugs and their mechanisms of action on living tissue F. Pharmacology: analysis of properties of chemicals that have a biologic action G. Pharmacotherapeutics: planned use and evaluation of the effect of drugs employed to prevent and treat disease H. Toxicology: analysis of poisons and poisonings caused by drugs DRUG EFFECTS A. Desired effect: (therapeutic effect) action for which the drug is given B. Adverse effect: action differing from the planned effect that is undesirable C. Side effect: often predictable outcome that is unrelated to the primary action of the drug D. Toxic effect: pathologic extension of the primary action of the drug E. Cumulation: elevation of circulating levels of a drug consequent to slowing of metabolic pathways or excretory mechanisms F. Drug dependence: driving need for continued use of a behavior – or mood altering drug that leads to abuse 1. Psychic dependence: craving requiring periodic or continued used of a drug for pleasure or relief of discomfort 2. Physical dependence: appearance of characteristic symptoms when drug use is suspended or terminated (withdrawal or abstinence symptoms) G. Hypersusceptibility: response to a drug action that is higher than that occurring when the same dosage is given to 90% of the population H. Idiosyncrasy: unpredictable, highly individualized response; generically conditioned enzymatic or receptor responsiveness that interferes with metabolic degradation of drug I. Paradoxical response: action of a drug producing a response that contrasts sharply with the usual therapeutic effect obtained with the same dosage of the drug J. Receptor: cellular site where union between a drug and a cellular constituent produces a reversible action K. Tolerance: lowering of effect obtained from an established dosage of a drug that necessitates raising the dosage to maintain the effect L. Tachyphylaxis: rapidly developing tolerance to a drug M. Drug allergy: Response occurring when drugs are from protein sources or combine with body protein and induce an antigen-antibody reaction that releases vasoactive agents. 1. Anaphylaxis: life-threatening episodes of bronchial constriction and edema that obstructs the airway and causes generalized vasodilatation that depletes circulating blood volume; occurs when a drug allergen is administered to an individual having antibodies produced by prior use of the drug 2. Urticaria: generalized pruritic skin eruptions or giant hives; occurs when a drug is administered to an individual having antibodies produced by prior use of the drug 3. Angioedema: fluid accumulation in periorbital, oral, and respiratory tissues with lengthening of the expiratory phase and wheezing as bronchial constriction gradually progresses; occurs when a drug is administered to an individual having antibodies produced by prior use of the drug 4. Serum sickness: gradually emerging intermittent episodes of dyspnea, hypotension, generalized edema, joint pain, rash, swollen lymph glands; occurs 7 or more days after initial administration of drug causing gradual low-level (titer) production of antibodies that interact with circulating drug to produce symptoms as long as the drug remains in the body 5. Arthus reaction: localized area of tissue necrosis caused by disruption of blood supply; occurs when spasticity, occlusion, and degeneration of blood vessels are precipitated by injection of a drug into a site having large quantities of bivalent antibodies 6. Delayed-reaction allergies: rash and fever occurring during drug therapy FACTORS INFLUENCING DOSAGE-RESPONSE RELATIONSHIP • Age, weight, sex, size, physiologic status, and genetic and environmental factors affect responses and dosage required for therapeutic effect. • The ratio between the median toxic dose and the median effective dose (TD50/ED50) of a drug provides the therapeutic index (TI), which is used as a guide to the safe, and the client’s status is monitored closely for evidence of drug-related adverse effects (e.g., antineoplastic drugs) • Concentration of active drug at receptors and duration of drug action are affected by: 1. Characteristics of the drug and the rate of absorption, distribution, biotransformation, and excretion 2. Drug affinity for particular tissues, immaturity of enzymes required for metabolism of the drug, or depressed function of tissues naturally metabolizing or excreting the drug • Membrane barriers: (e.g., placental or blood-brain) may block or selectively pass the drug from the circulating fluids to protect areas • Plasma protein binding of drugs maintains tissues levels by liberating the drug when stores are lowered and by slowing renal clearance until the drug is freed from binding sites DRUG INTERACTIONS A. Drugs and foods may interact to affect the therapeutic plan adversely (e.g., ingestion of foods or vitamin preparations containing vitamin K may inhibit the hypothrombinemic effect of oral anticoagulants) B. Drugs antagonism: opposing effects of two drugs at receptor sites in body tissues 1. Chemical antagonism: combining or binding of two drugs causing inactivation of the chemicals 2. Pharmacologic antagonism: competition of two drugs for receptor that may allow the weaker drug to block access by the more potent drug 3. Physiologic antagonism: opposing action on physiologic systems that allows cancellation of action by either drug. C. Drug action summation: combined or concurrent action of drugs that increase therapeutic effects or incidence of adverse effects 1. Synergism: interaction of drugs at common receptor sites that alters metabolism or excretion and enhances the effect of drugs 2. Addition: action of two drugs at different receptors that produces an effect twice that possible when either drug is used alone 3. Potentiation: intensified action occurring when two drugs are administered concurrently that is greater than when either drug is administered alone. NURSING REPONSIBILITIES A. Increasingly, as part of nursing care the nurse assumes the responsibility of administering a greater number of medication in a greater variety of forms via a greater assortment of routes; many of these substances have a narrow therapeutic index, increasing the nursing responsibilities associated with their administration B. In the interest of client welfare and safety, it is imperative that the independent and collaborative responsibilities inherent in this function be understood and practiced C. Ascertain the presence and correctness of a legally written order D. Know the common symbols and equivalents in the apothecary and metric systems E. Know the common abbreviations denoting frequency and route of administration F. Know the usual dosage of a drug, the usual route of administration, and the expected, unusual, untoward, or toxic effects of drug G. Monitor serum-drug levels for 1. Attainment of therapeutic level 2. Toxic level 3. Peak and trough levels H. Use independent judgment before administering a medication by assessing 1. The client’s needs relative to factors such as prn medication and expected effects of the medication (e.g., diuresis or sleep) 2. Untoward or toxic manifestations of prior dose (e.g., pruritis following an antibiotic, bradycardia and visual disturbances with digoxin) 3. Compatibility of medications administered at the same time a. The presence of clouding or a precipitate when mixing injectables (e.g., Phenobarbital [Luminal Sodium] and meperidine [Demerol] b. Inhibition of medication (e.g., antacids or milk given with tetracycline interferes with absorption, resulting in decreased serum levels of the antibiotic) c. Potentiation of another medication (e.g., ASA given when a client is receiving anticoagulants intensifies the anticoagulant effect) 4. Compatibility of medication with substances in the diet or environment 5. Effects on living tissues a. Iron can discolor tissue and must be given through a straw in liquid form or by the Z-track method intramuscularly b. Abscess formation can occur when the same area is used too often for intramuscular administration; thus rotation of site is necessary c. Pain, irritation, or inflammation can occur during intravenous administration and may necessitate adjustments such as greater dilution or slower flow rate I. Help the client accept ordered medications by independent actions such as 1. Crushing tablets that cannot be swallowed 2. Disguising unpalatable tastes with fruit juices 3. Reinforcing the need for medication J. Ensure that the right medication is given to the right client at the right time in the right dose and by the right route. 1. Verify orders 2. Read labels 3. Calculate the dosage accurately when prescribed dose is not available 4. Pour or draw up correct amounts 5. Identify the client correctly by checking the armband 6. Prepare the client psychologically by providing explanations as needed 7. Prepare the client physically by a. Positioning appropriately for oral and parenteral medications b. Disinfecting the skin when it is to be punctured 8. Use clean or sterile technique as indicated by route of administration; use universal precautions 9. Use the route specified as appropriate for the ordered medications and dosage 10. Recognize that the client has the right to refuse medication K. For assistance with calculation of solutions and dosages, use ratio and proportion: Desired dosage: available dosage =Desired amount L. Use the appropriate technique for administration 1. Preparations: such as tablets, capsules, pills, powders, or liquids may be swallowed: in addition a. Tablets (e.g., nitroglycerine) may be held sublingually b. Powders (e.g., cromolyn sodium) may be inhaled with a medihaler c. Liquids may be nebulized and inhaled or may be swabbed, sprayed, or instilled d. Sustained-release or enteric-coated preparation should not be crushed or broken open e. Suspensions should be shaken well before pouring 2. Parenteral preparations such as ampules or vials containing the dose in solution or power to which sterile water or saline must be added may be given in several ways: a. Subcutaneously or hypodermally in small volume (0.5to2 ml) 1Pinch the tissue on the outer surface of the upper arm (deltoid), the anterior aspect of the thigh (vastus lateralis and rectus femoris), or the abdomen 2.Insert a 25 to 27 –guage needle 5/8 to 1inch in length at a 45-to 60-degree angle, or a 1/2 –inch needle (insulin or tuberculin) at a 90-degree angle, aspirate slightly and inject the medication if there is no blood return (aspiration not indicated when heparin administered because of bruising; aspiration when insulin is administered is controversial) 3.Massage to increase absorption (contraindicated when giving heparin) b. Intramuscularly in slightly larger volume (upto 5ml) 1.Spread the tissue taut or pinch if necessary 2.Use the upper outer quadrant of the buttock, gluteal muscle, the vastus lateralis, or the deltoid area of the arm 3.When using the gluteal muscle, promote relaxation of the muscle whenever possible by placing the client in a prone position with toes pointing inward or on the side with upper leg flexed 4.Insert 20 to 22 guage needle 1 to 1/2 inches in length at a 90-degree angle quickly and smoothly 5.Depth of insertion depends on factors such as weight of the client and size of the muscle used 6.Aspirate when the needle is in place and tissue is released (unless giving a substance such as non-dextran [inferon](unless giving a substance such as iron-dextran [inferon], for which the Z-track method is used) a. If no blood returns, continue injection b. If blood is aspirated, withdraw and prepare a fresh dose 7.Apply pressure or message area after injection as required (unless contraindicated, e.g., Z-track technique 8.Avoid injecting in to edematous areas because edema delays absorption c. Intradermally with very small volume for local effect 1. Use syringe with appropriate calibrations (e.g., tuberculin) 2. Inject at a 15- degree angle using a 26-gauged needle, 3/8 to 1/2 in length with the bevel up d. Piggybag administration using intravenous tubing in place use sterile technique 1. If necessary, dilute medication according to directions add 50 –150ml of fluid 2. Remove air from tubing of piggybag without losing any fluid 3. Cleanse diaphragm on intravenous tubing already in place with alcohol 4. Insert piggybag in rubber diaphragm on tubing leading from the infusion that is keeping the vein open 5. Stop flows of or lower the primary solution below level of the piggybag 6. Adjust rate of flow on piggybag medication to complete absorption in time designated –usually about 30 –45 minutes 7. Remove the piggybag adjust flow rate 3. Transdermal preparations a. Medication should not been touched during preparation for administration; gloves should be worm with certain medications b. Medications should be applied to a smooth, hairless body surface; sites should be rotated c. Remove old transdermal application before applying a new one M. Clearly and accurately record and report the administration of medications and the client’s response. Drugs acting on neuromuscular function 1. Spasticity refers to a state of sudden, involuntary muscular contraction involved in a variety of musculoskeletal conditions. Spasmolytics are used to reduce spasticity. 2. Paralysis refers to loss of function. Neuromuscular-blocking agents are used to cause paralysis to facilitate surgery and mechanical ventilation. 3. Neuromuscular-blocking agents that are termed non-depolarizing prevent neutral communication from depolarizing the muscle. In other words, the muscle remains in a relaxed state. 4. Depolarizing drugs cause muscle depolarization and prevent repolarization. That is, depolarizing agents cause the muscle to contract 5. Neuromuscular blockers are not mediated by the central nervous system. Rather, they work by directly interfering with transmission at the end plate, which is the site of communication between a nerve and a muscle. 6. Whereas depolarizing NMJ blockers represented by succinylcholine. Centrally acting spasmolytics are represented by baclofen, whereas peripherally acting spasmolytics are represented by dantrolene. 7. Succinylcholine, a depolarizing agent, is used for short inductions, endotracheal intubation, and endoscopy. Tubocurarine, pancuronium, and pipecuronium are nondepolarizing agents. Dantrolene is a peripherally acting spasmolytic. Drugs acting on the urinary system Diuretics promote the excretion of sodium and water from the body, whereas beta-blockers have been proved to slow heart rate, decrease cardiac output, and lower blood pressure. Calcium channel blockers decrease mechanical contraction of the heart, reduce automaticity, lessen conduction velocity, but do not reduce cardiac output, whereas ACE inhibitors prevent vasoconstriction by affecting the reninangiotensin-aldosterone system. 1. Captopril should be taken 1 hour before meals, because food decreases absorption, and it has been demonstrated to cause fetal injury and death during the second and third trimesters. The patient should take first dose at bedtime to minimize the possibilities of injury due to first dose hypotension, and a chronic cough is a significant adverse effect. 2. Measures to manage symptoms of orthostatic hypotension can be managed by teaching the patient to change positions slowly after lying down by sitting on the edge of the bed for a few minutes before standing, if possible, the patient should avoid standing in one position for any length of time to prevent episodes of hypotension resulting from venous pooling. 3. Diuretics work in the nephron. Different diuretic drugs work in different parts of the nephron. Hydrochlorothiazide is the prototype thiazide, triamterene is the prototype potassium-sparing diuretic, and mannitol is the prototype osmotic diuretic, and acetazolamide is the prototype carbonic anhydrase inhibitor. 4. Mannitol is used to treat acute renal failure whereas carbonic anhydrase inhibitors are used to treat open-angle glaucoma. Diuretics are used to treat hypertension, and diuretics are not used to treat acid-base imbalances. 5. Oliguria is demonstrated by urine output of less than 400 ml /day, whereas anuria is demonstrated by less then 250 mL/day. Adequate urine output must equal 30 ml/hr, or 720 ml in 24 hours. 6. Hydrocholrothiazide may be administered in the morning so that the maximum diuretic effect will not disturb sleep (assuming the patient is awake days and sleeps nights), and a weight gain exceeding 3 pounds in 1 day should be reported to the prescriber. The patient should be taught strategies for coping with mouth dryness (chewing gum, sucking ice chips or hard candies), and consume potassium-rich foods and beverages since potassium may be wasted by therapy. 7. Triamterene, a potassium-sparing diuretic, should be taken in the morning so that increased diuretic effect occurs during waking hours. Patients should report a weight gain of 3 pounds or more in 1 day. The patient should also be taught to use chewing gum or suck hard candies to relieve dry mouth. 8. If urine output does not range between 30 and 50 mL/h after two test doses of mannitol, the drug should not be used. Urine output of 100 mL/h indicates that the mannitol may be continued as ordered. 9. The prototype osmotic diuretic mannitol is, structurally, a sugar. Other osmotic diuretic agents are glycerin and urea. Albumin is a plasma protein. 10. Symptoms of diuretic overdose are: • Severe hypotension • tachycardia • Severe dizziness or syncope • Deafness or ringing in the ears • Excessive thirst • Poor skin tension • Muscle cramps or weakness • Drowsiness • Weak pulse • Confusion • Cardiac arrest prolonged unconsciousness Drug Therapy In Urinary Disorders In acute cases, an appropriate drug may be started as soon as the urine has been collected for bacteriological examination. When the results of drug sensitivity of the pathogen grown are available, another drug may be substituted for the first one, if necessary. Although the symptoms are relieved quickly, the pyuria takes a longer time to clear. In chronic cases, mixed infection is more likely and concomitant renal failure may modify drug therapy. In such cases, there is no desperate hurry to start drug treatment before the case is thoroughly investigated. Drugs may be bactericidal or bacteriostatic. The former are more capable of eradicating the infection. The growth of E.coli is optimum at pH 6.0 to 7.0 and is inhibited at pH below 5.5 and above 7.5. The pH of the urine must also be maintained at a level that would permit optimum antibacterial activity .It must be emphasized that infections due to proteus and sometimes other coliforms, Staph. albus and some diphtheroids, give rise to alkaline urine. This is because these organisms produce urease, an enzyme that splits urea to form ammonia. As frequent emptying of the bladder (every 2-3 hours) helps to reduce the bacterial counts in the urine and as the growth of E.coli is reduced if the urine is very dilute, the fluid intake should be liberal during the use of most of the drugs. All pregnant women should be screened for bacteriuria in the first trimester and should be treated if necessary, to reduce increased risk of acute pyelonephritis and of low birth weight of their infants. In such cases, a 7-14 day course is recommended. After successful treatment, the subject should be followed in order to detect any recurrence. The drugs, which are usually employed in the urinary tract infections, are: 1.Bacteriostatic agents such as sulfonamides, tetracyclines and nitrofurantoin. 2.Bactericidal agents such as cotrimoxazole, ampicillin, extended spectrum penicillins, aminoglycosides, fluoroquinolones and cephalosporins. Drugs, which act as antibacterial agents only in the urinary tract (nitrofurantoin, methenamine mandelate and nalidixic acid) are sometimes called urinary antiseptics. They are bacteriostatic. Sulphonamides Sulfonamides are effective against most of the common urinary pathogens including E. coli. They produce effective urine and tissue levels. They can eradicate uncomplicated E. coli infections but are relatively ineffective in chronic cases, complicated cases or in the presence of mixed infections. A short acting sulfonamide such as sulfisoxazole should be administered in a dose of 2 g. initially, followed by 1 g. 6 hourly daily for 7-10 days. Urinary pH should be alkaline during such therapy and fluid intake must be liberal. This initial treatment may be followed by 1 g. daily for several months. Nitrofurantoin (Furadantin) : This drug is rapidly absorbed from the gastrointestinal tract. It has mainly a bacteriostatic effect against common urinary pathogens except some strains of Proteus and most strains of Pseudomonas against which it is ineffective. Dose: Nitrofurantoin given in the dose of 50 – 100 mg/day can be administered for several weeks to months for ‘chronic suppressive therapy’. The drug, therefore should not be used in cases of renal insufficiency (creatinine clearance 20ml/minute or less) Tetracycline: These drugs are bacteriostatic and along with chloramphenicol are termed broad-spectrum antibodies, as in addition to their antibacterial activity against a number of Gram-positive and Gram-negative organisms; they also inhibit the growth of certain organisms. Tetracycline interferes with protein synthesis by blocking the attachment of aminoacyl transfer RNA to the acceptor site on the messenger RNA-ribosome complex. Tetracyclines, in general, have a low toxicity when used in recommended dosages. The adverse effects are: • Skin rashes • Nausea, vomiting, epigastric distress, loose stools • Suppression of the normal intestinal flora with resultant superinfection • Fatal hepatic dysfunction • Aggravation of azotemia • Calcification in bones and teeth. • Yellow staining of the teeth of the infant; defective formation of enamel and hypoplasia of the teeth may also occur. • Pigmentation of permanent teeth and increased risk of caries may occur in children receiving long or short-term therapy with tetracyclines. • Should be avoided in infants and in children upto the age of 12 years. • Deposited in fetal bones and may reduce their linear growth. • Some patients, particularly infants, treated with tetracyclines may develop increased intracranial pressure. • Local thrombosis: interfere with blood coagulation. • Uremic patients may develop peptic ulcers. Preparations and dosage: For oral use, usually they are supplied as capsules or tablets containing 250 mg., as pediatric syrup containing 125-mg/5 ml. The adult dose varies between 1 and 2 g. per day in 3 – 4 divided doses; for children 15 – 25 mg/kg body weight, daily in divided doses. I.M. and I.V. administration: The usual I.M. dose is 100 mg at 8 hourly intervals. The total daily I.V. dose of oxytetracycline and tetracycline for most acute infections in adults is 1-2 g. in two equal doses at 12 hourly intervals. The tetracyclines are never administered intrathecally. Nalidixic Acid: It is a 4-quinolone derivative. As suggested by its trade name, nalidixic acid is effective against certain gram-negative bacteria, especially E. coli and shigella. It is relatively ineffective against gram-positive organisms. The drug acts by interfering with the synthesis of nucleoprotein (DNA). It is bactericidal. Nalidixic acid is readily absorbed from the gastrointestinal tract. Adverse reactions: Nausea, vomiting and diarrhoea, pruritus, urticaria, fever, eosinophilia headache, malaise, drowsiness, myalgia. Convulsions may appear with over dosage, particularly in children. Dose: Nalidixic acid is available as 250 and 500 mg tablets and as syrup. The usual adult dose is 4 g. daily in 4 divided portions. C.I.: Severe cerebral arteriosclerosis, Parkinsonism, impairment of hepatic and/or renal functions history convulsive seizures, during pregnancy. Co-trimoxazole (Septran, Bactrim): The combination of sulfamethoxazole and trimethoprim is a highly potent, bactericidal combination against urinary tract infections with E. coli and is preferred to a sulfonamide alone. It is also effective against Proteus species but not against Pseudomonas. In acute uncomplicated urinary tract infection, it is used in the dose of 2 tablets twice a day for 7-10 days. In smaller doses (as low as one tablet twice a week) it has been claimed to be effective in eliminating chronic bacteriuria. It should be avoided during pregnancy. As trimethoprim concentrates in the prostate much better then most other drugs, cotrimoxazole has been used successfully in eradicating the prostatic focus of infection, which is often responsible for recurrent urinary tract infection in adult men. Ampicillin: Ampicillin is effective both orally and parenterally. It is bactericidal to E. coli, Aerobacter and certain strains of Proteus. When used in a dose of 0.5g six hourly for 7-10 days, it is capable of totally eradicating majority of urinary tract infections due to E. coli. It is useful for treatment of urinary tract infections in pregnant women. Aminoglycoside antibiotics: Gentamicin is the only aminoglycoside commonly used in U.T.I. It is effective against E. coli, Proteus and Pseudomonas. It has the disadvantage that it has to be given parenterally. It can cause ototoxicity and renal toxicity. Its use should be reserved for complicated urinary tract infection. Cephalosporins: Cephalosporins possess a wide range of activity against Gram positive and Gram-negative bacteria. The Gram-negative organisms susceptible to these antibiotics include E. coli Proteus mirabilis, K. pneumoniae, and N. gonorrhea. These drugs are valuable in infections with E. coli and Proteus resistant to other antibiotics. They are the drugs of choice in klebsiella infections. Cephalosporins are particularly indicated in septicemic urinary tract infections. Cephalosporins act by inhibiting bacterial cell wall synthesis in a manner similar to penicillins, and are bactericidal. Adverse reactions: In general, cephalosporins are well tolerated. • Local reactions: I.M. injections are painful and I.V. injections can cause thrombophlebitis. • Allergy: Skin rash, fever, eosinophilia, neutropenia • Superinfection • Nephrotoxicity: Large doses can cause kidney damage. • CNS toxicity: Cerebral irritation, nystagmus and hallucinations • Blood toxicity The first generation cephalosporins are effective against staphylococci, pneumococci, streptococci and the common gram-negative pathogens such as E. coli, Klebsiella and Proteus. However, they are not effective against salmonella, shigella, anaerobes and pseudomonas. Eg. Cephalexin and cefadoxi The second generation cephalosporins offer a wider coverage against gram-negative bacilli than the first generation cephalosporin. Their main use would appear to be in the gram-negative infections, especially those caused by beta lactamase producing organisms, including H.influenzae. Cephazolin is considered the agent of choice for antimicrobial prophylaxis in most surgical procedures. The third generation cephalosporins have poor activity against the gram-positive cocci but are more active against the gram-negative bacilli than the first and second generation cephalosporins Eg: Cephtriaxone Fourth generation cephalosporin: cefepime is a new cephalosporin with properties like those of the third generation cephalosporins Treatment of Lower U.T.I Acute uncomplicated cystitis-urethritis in females: The first attack in a young, healthy women is treated by some physicians with a single dose regimen: sulfisoxazole 2g orally; cotrimoxazole 6 tablets orally; or ampicillin/ amoxycillin 3g orally. Although such therapy is effective in many cases, it gives low cure rates and leads to frequent recurrences especially with drugs such as amoxycillin and oral cephalosporins, which are excreted rapidly. Hence, a 3 day regimen appears optimum. Cotrimoxazole is perhaps the best choice for empirical 3 day therapy. In all other situations, a 7-14 day regimen is indicated. These situations are: • Failure of the 3 day regimen • Symptomatic in both men and women • Pregnant women • Children • Patients with underlying renal disease or urinary tract obstruction/ abnormalities. The regimens are shown in • Trimethoprim 100 mg b.i.d. • Cotrimoxazole 2 tablets b.i.d. • Ampicillin 250-500 mg q.i.d.; and • Cephalexin 500 mg. Q.i.d. Norfloxacin 400 mg b.i.d, ciprofloxacin 250mg b.i.d. or carbenicillin indanyl 2 tab b.i.d. may be used in infections caused by Ps.pyocyaneus and other resistant organisms. Recurrent infection manifested by repeated bacteriuria usually within a month of apparently successful treatment, is caused by identical organisms. Hidden source of infection or a urological abnormality should be looked for in such patients. The use of diaphragm and spermicides has been associated with recurrences in some patients probably because spermicides encourage bacterial colonization of the vagina with E.coli. Recurrence should be documented by a culture at least once before starting treatment. Such women should receive treatment for at least 4-6 weeks with either cotrimoxazole or a fluoroquinolone. The importance of eliminating the vaginal colonization by E.coli has already been discussed. In patients with suspected prostatic focus of infection, drugs like trimethoprim, erythromycin (for gram positive bacteria), fluoroquinolones or doxycyline and aminoglycosides are recommended. Despite prolonged (6-12) therapy with these agents, failure rates in treating men with chronic bacterial prostates are usually 30-40%. It should be remembered that non-bacterial prostatitis is far commoner than proven bacterial prostatic. The entity is defined by evidence of prostatic inflammation but negative cultures of urine and prostatic fluid in a man with various genitourinary symptoms. Its cause is unknown. Where bacteriuria cannot be eradicated, chronic suppressive therapy with 1 tablet of cotrimoxazole or 50-100mg of nitrofuratoin per day can suppress symptomatic infection. Trimethoprim alone should not be used for this purpose for fear of development of drug resistance. Chronic persistent infection with pyuria and bacteriuria commonly occurs in patients with indwelling catheters. In such patients, only acute symptomatic infections should be treated with one of the 7-14 day regimens given above. Long term continued administration of antibacterial agents only leads to the emergence of drug resistant organisms. Bladder washes with 1:10,000 chlorhexidine is a better alternative to the continuous long term use of systemic antibacterial agents. Further, the indwelling catheters should be used sparingly and only when they are a must. Asymptomatic bacteriuria: Several studies have shown that asymptomatic bacteriuria is often transient and resolves without treatment. The available data do not support routinely treating all men with asymptomatic bacteriuria. Treatment is appropriate before genitourinary tract, in infection with microorganism with special virulence such as urea-splitting bacteria and in immunocompromised host. However, children and pregnant women with asymptomatic bacteriuria must be treated adequately to prevent chronic renal infection. Post-coital cystitis: Some women seem to get a lower U.T.I. following every sexual intercourse and in some of them it may produce urgent symptoms. Such a patient should be initially treated by a full course of a suitable antibacterial drug. Following this, she should be advised to apply 0.5% cetrimide cream to the periurethral area before coitus and to empty her bladder immediately after the sexual act. This may be followed by a single dose of ampicillin 250mg., nitrofurantoin 100 mg., or a cotrimoxazole tablet after each coitus. Acute urethral syndrome occurs commonly in women and is often due to chlamydial infection (nongonoccocal urethritis). Treatment of upper U.T.I. This is usually due to the same pathogens that cause lower U.T.I. but is a more serious condition. Acute pyelonephritis is commonly associated with a predisposing factor such as an obstructive uropathy or diabetes mellitus (complicated U.T.I.). The patient may be septicaemic and severely ill. Urine and blood cultures are mandatory before starting the antibacterial therapy; the results of the tests may be helpful in modifying the initial therapy, which is started without waiting for the culture report. The drugs used are: cotrimoxazole orally or I.V. (especially in infections due to enterobacter); or a cephalosporin, drug regimens useful in such cases are (either cotrimoxazole or gentamicin)=(either ampicillin or a cephalosporin) for 14 days. Ciprofloxacin or extended spectrum penicillin may have to be used in infections due to highly resistant organisms. If fever and flank pain persist after 3 days of therapy, urine culture should be repeated and ultrasonography should be carried out to rule out a perinephric or intrarenal abscess, or a urological abnormality. Follow up urine culture is recommended after 2 weeks of therapy. Drugs therapy is given usually for 14 days, but occasionally longer treatment may be required. Fluoroquinolones should not be used in pregnant women. In severely ill, hospitalized patients, the initial empiric therapy should be with either ampicillin + gentamicin or imepenam + cilastatin for adequate cover of most of the common organisms including Ps. aeruginosa. A urine culture should be done 1-2 weeks after completing the therapy. Chronic pyelonephritis: This is a serious condition, which can lead to chronic renal failure. An underlying cause such as obstruction must be carefully searched for in all cases. The antibacterial drug treatment must be prolonged and the choice of the drug is governed by the identity of the organisms and their drug sensitivity, and by the extent of renal impairment, if present (see below). Complicated U.T.I. is difficult to treat. It is important to detect drug failure early so that an ineffective drug is not continued; its continuation will only help super infection with more resistant microorganisms to establish, and add to the cost of the therapy. In such cases, it may be better to leave the infection untreated except managing acute episodes. Suppressive therapy is rarely effective. Renal impairment: Tetracyclines, except doxycycline, must be avoided in chronic renal failure. The dose of aminoglycosides and cephalosporins must be scaled down. Nitrofurantoin and nalidixic acid do not achieve adequate urinary concentration in patients with renal failure; further, their systemic toxicity is increased in such patients. Tetracyclines and fluoroquinolones should be avoided in children. Tetracyclines, cotrimoxazole, nitrofurantoin and fluoroquinolones should be avoided during pregnancy. Fluoroquinolones should be reserved for complicated and resistant U.T.I.; they should not be used routinely in uncomplicated U.T.I. for fear of development of drug resistant organism. They are also expensive at present. Follow up: Patients with acute urinary tract infection should be followed up for at least 6 months after treatment and urine cultures should be repeated at 1-2 month intervals. Cases with recurrent acute infection or with chronic infection need prolonged suppressive drug therapy (6-12 months) after the initial treatment; in these cases, follow up cultures at regular intervals should be done for about two years. It has been demonstrated that untreated kidney infection not only leads to chronic pyelonephritis but also prevents the kidney growth in children. Results in children with kidney infections indicate that daily sulfisoxazole (0.25gm at less than 1 year; 0.5 gm at 1 to 5 years and 1gm at more than 5 years of age) or nitrofurantoin (2-4mg/kg), given for a prolonged period, reduces markedly the incidence of pyelonephritis and helps to restore the kidney growth. Ampicillin is probably better and safer for this purpose. Patients with vesicoureteral reflux should be taught the practice of ‘double micturition’ to minimize residual bladder urine. Prophylactic antibacterial therapy: This is indicated under the following circumstances: Following instrumentation of the urinary tract, and in patient with uncorrectable congenital anomalies of the urinary tract. Co-trimoxazole, nitrofurantoin and ampicillin are the most commonly employed agents for this purpose. It must be remembered, however, that doses which are employed for long term suppressive therapy may not produce adequate tissue levels Thus, although the urine may remain sterile, a renal infection may continue to progress without being detected. Short-term catheterization may not be covered by giving the patient nitrofurantoin or by washing the bladder with chlorhexidine 1:10,000 solution. Intermittent catheterization has been shown to cause a lower incidence of bacteriuria than long-term indwelling catheterization. During long-term catheterization, measures such as closed drainage are far more important than drugs. Phenazopyridine (Pyridium, Pyridacil): This azo dye is used in the dose of 200mg three times a day to relieve pain, burning, urgency and frequency associated with lower urinary tract infection (cystitis, prostatitis and urethritis). It does not act as a urinary antiseptic but can give symptomatic relief. The drug colors the urine red or orange and can stain clothing. Therapy with this drug is generally limited to one week. Nursing Care in Drug Therapy for renal drugs Furosemide (Frusemide) Apo-Furosemide, Furoside, Lasix, Lasix Special, Myrosemide, Novosemide, Uritol. Pharmacologic class: loop diuretic Therapeutic class: diuretic, antihypertensive Pregnancy risk category: C Nursing Process Assessment • Assess patient’s underlying condition before starting therapy. • Monitor weight, peripheral edema, breath sounds, blood pressure, fluid intake and output, and electrolyte, glucose, BUN, and carbon dioxide levels. • Monitor uric acid level, especially if patient has a history of gout. • Be alert for adverse reactions and drug interactions. • Assess patient’s and family’s knowledge of drug therapy. Nursing diagnoses • Excessive fluid volume related to presence of edema • Impaired urinary elimination related to diuretic therapy • Deficient knowledge related to drug therapy Planning and implementation • Give a P.O. or I.M. dose in the morning to prevent nocturia. Give a second dose in early afternoon. • Store tablets in light-resistant container to prevent discoloration. Don’t use yellowed injectable preparation. • Refrigerate oral furosemide solution to ensure drug stability. • If oliguria or azotemia develops or increases, notify prescriber. Patient teaching • Advise patient to stand slowly to prevent dizziness, not to drink alcohol, and to minimize strenuous exercise in hot weather. • Instruct patient to report ringing in ears, severe abdominal pain, or sore throat and fever because they may indicate toxicity. Alert: Discourage patient from storing different drugs in same container because this increases risk of errors. The most popular strengths of furosemide and digoxin are white tablets of similar size. • Tell patient to check with prescriber before taking OTC medications or herbal remedies. Evaluation • Patient is free from edema. • Patient demonstrates adjustment of lifestyle to cope with altered patterns of urinary elimination. • Patient and family state understanding of drug therapy. Iron dextran DexFerrum, Dexlron, InFeD Pharmacologic class: parenteral iron supplement Therapeutic class: hematinic Pregnancy risk category: C Nursing process Assessment • Assess patient’s iron deficiency before starting therapy. • Monitor the drug’s effectiveness by evaluating hemoglobin level, hematocrit, and reticulocyte count, and monitor patient’s health status. • Be alert for adverse reactions and drug interactions. • Observe patient for delayed reactions (1 to 2 days), which may include arthralgia, backache, chills, dizziness, headache, malaise, fever, myalgia, nausea, and vomiting. • Assess patient’s and family’s knowledge of drug therapy. Nursing diagnoses • Ineffective health maintenance related to iron deficiency • Risk for injury related to potential drug induced anaphylaxis • Deficient knowledge related to drug therapy Planning and implementation • Don’t give iron dextran with oral iron preparations. • I.M. or I.V. injections of iron are recommended only for patients for whom oral administration is impossible or ineffective. Alert: I.M. or I.V. test dose is required. • When giving I.M., use a 19G or 20G needle that is 2 to 3 inches long. Inject drug deep into upper outer quadrant of buttock – never into arm or other exposed area. Use Z-track method to avoid leakage into S.C. tissue and staining of skin. • Minimize skin staining by using separate needle to withdraw drug from its container. • Keep epinephrine and resuscitation equipment readily available to treat anaphylaxis. Patient teaching • Warn patient to avoid OTC vitamins that contain iron. • Teach patient to recognize and report symptoms of reaction or toxicity. Evaluation • Patient’s hemoglobin level, hematocrit, and reticulocyte count are normal. • Patient doesn’t experience anaphylaxis. • Patient and family state understanding of drug therapy. Desmopressin acetate DDAVP, Stimate Pharmacologic class: posterior pituitary hormone Therapeutic class: antidiuretic, hemostatic Pregnancy risk category: B Nursing process Assessment • Obtain history of patient’s underlying condition before therapy. • Monitor effectiveness for diabetes insipidus or relief of symptoms of other disorders by checking patient’s fluid intake and output, serum and urine osmolarity, and urine specific gravity. • Be alert for adverse reactions and drug interactions. • Monitor patient carefully for hypertension during high-dose therapy. • Assess patient’s and family’s knowledge of drug therapy. Nursing diagnoses • Deficient fluid volume related to underlying condition • Acute pain related to drug-induced headache • Deficient knowledge related to drug therapy Planning and implementation • When giving S.C., rotate injection sites. • Follow manufacturer’s instructions exactly for intranasal administration. • Ensure nasal passages are intact, clean, and free of obstruction before intranasal use. • Intranasal use can changes in nasal mucosa, resulting in erratic, unreliable absorption. Report worsening condition to prescriber, who may prescribe injectable DDAVP. • Don’t use drug to treat severe cases of von Willebrand’s disease or hemophilia A with factor VIII levels of 0% to 5%. • Patients may be switched from intranasal to S.C. form, such as during episodes of rhinorrhea. Give 1/10 or ¼ of their usual nasal dose S.C. • When drug is used to treat diabetes insipidus, adjust dosage according to patient’s fluid output. Adjust morning and evening doses separately for adequate diurnal rhythm of water turnover. Alert: Don’t confuse Desmopressin with vasopressin. Patient teaching • Instruct patient to clear nasal passages before using intranasal form of the drug. • Teach patient and caregiver correct method of administration. Patient may have trouble measuring and inhaling drug into nostrils. • Advise patient to report conditions such as nasal congestion, allergic rhinitis, or upper respiratory tract infection because dose adjustment may be required. • Teach patient using S.C. Desmopressin to rotate injection sites to avoid tissue damage. • Warn patient to drink only enough water to satisfy thirst. • Inform patient that when treating hemophilia A and von Willebrand’s disease, giving desmopressin may avoid hazards of using blood products. • Advise patient to wear or carry medical identification indicating use of drug. Evaluation • Patient’s achieves normal fluid and electrolyte balance. • Patient states that headache is relieved with mild analgesic. • Patient and family state understanding of drug therapy. Norfloxacin Noroxin Pharmacologic class: fluoroquinolone Therapeutic class: broad-spectrum antibiotic Pregnancy risk category: C Nursing process Assessment • Assess patient’s infection before starting therapy regularly thereafter to monitor the drug’s effectiveness. • Obtain a sample for culture and sensitivity test before starting therapy, and repeat p.r.n. throughout therapy. May begin therapy pending test results. • Be alert for adverse reactions and drug interactions. • Assess patient’s and family’s knowledge of drug therapy. Nursing diagnoses • Infection related to bacteria • Risk for injury related to drug-induced adverse CNS reactions • Deficient knowledge related to drug therapy Planning and implementation • Give drug on empty stomach. • Make sure patient is well hydrated before and during therapy to avoid crystalluria. Alert: Don’t confuse Noroxin with Neurontin or Floxin. Patient teaching • Urge patient to take 1 hour before or 2 hours after meals to promote absorption • Warn patient not to exceed recommended dosage. • Encourage patient to drink several glasses of water throughout day to maintain hydration and adequate urine output. • Warn patient to avoid hazardous activities until the drug’s CNS effects are known. Evaluation • Patient is free from infection • Patient has no injuries from drug-induced adverse CNS reactions. • Patient and family state understanding of drug therapy. Cyclophosphamide Cycloblastin, Cytoxan, Cytoxan Lyophilized, Endoxan-Asta, Neosar, Procytox. Pharmacologic class: alkylating drug Therapeutic class: antineoplastic Pregnancy class: D Nursing process Assessment • Assess patient’s underlying condition before therapy and regularly during therapy. • Monitor CBC, uric acid levels, and renal and liver function tests. • If corticosteroid therapy is stopped, monitor patient for cyclophosphamide toxicity. • Be alert for adverse reactions and drug interactions. • Assess patient’s and family’s knowledge of drug therapy Planning and implementation • Tablets are used for children with “minimal charge” nephritic syndrome, not to treat neoplastic disease. • To prevent hyperuricemia with resulting uric acid nephropathy, allopurinol may be used with adequate hydration. Patient teaching • Warn patient that alopecia is likely to occur but that it’s reversible. • Warn patient to watch for signs of infection (fever, sore throat, fatigue) and bleeding (easy bruising, nosebleeds, bleeding gums, melena) and to take temperature daily. • Instruct patient to avoid OTC products that contain aspirin. • Encourage patient to void every 1 to 2 hours while awake and to drink at least 3 L of fluid daily to minimize risk of hemorrhagic cystitis. Tell patient not to take drug at bedtime because infrequent urination during night may increase possibility of cystitis. If cystitis occurs, tell patient to stop drug and notify prescriber. Cystitis can occur months after therapy ends. Mesna may be given to lower risk and severity of bladder toxicity. • Advise both men and women to practice contraception while taking drug and for 4 months after because drug is potentially teratogenic. • Advise women of childbearing age to avoid becoming pregnant during therapy. Also recommend consulting with prescriber before becoming pregnant. Evaluation • Patient shows positive response to drug therapy. • Patient doesn’t experience injury as a result of drug-induced adverse reactions. • Patient and family state understanding of drug therapy. Phenazopyridine Hydrochloride (phenylazo diamino pyridine hydrochloride) Azo-Dine, Azo-Gesic, Azo-Standard, Baridium, Geridium, Phenazo, Prodium, Pyridate, Pyridium, Pyridium Plus, RE-Azo, Urodine, UTI Relief Pharmacologic class: azo dye Therapeutic class: urinary analgesic Pregnancy risk category: B Nursing Process Assessment • Assess patient’s pain before and after giving drug. • Be alert for adverse reactions • If nausea occurs, monitor patient’s hydration • Assess patient’s and family’s knowledge of drug therapy. Nursing diagnoses • Acute pain related to underlying urinary tract condition • Risk for deficient fluid volume related to drug induced nausea • Deficient knowledge related to drug therapy Planning and implementation • Administer drug with food to minimize nausea. Alert: Don’t confuse Pyridium with pyridoxine, pyrimethamine, or pyridine. • Advise patient that taking drug with meals may minimize nausea. • Tell patient to stop taking drug and notify prescriber if skin or sclera becomes yellow-tinged. • Warn patient that drug colors urine red or orange. It may stain fabrics and contact lenses. • Tell patient to notify prescriber if urinary tract pain persists after 2 days and the patient isn’t also taking an antibiotic. If using drug with an antibiotic, stop drug after 2 days because it has no additional effectiveness. Drug isn’t for long-term use. Evaluation • Patient is free from pain. • Patient maintains adequate hydration. • Patient and family state understanding of drug therapy. Oxybutnin chloride Apo-Oxybutynin, Ditropan, Ditropan XL, Oxytrol Pharmacologic class: synthetic tertiary amine Therapeutic class: urinary antispasmodic Pregnancy risk category: B Nursing process Assessment • Assess patient’s bladder condition before starting therapy. • Before giving drug, confirm neurogenic bladder by cystometry and rule out partial intestinal obstruction in patients with diarrhea, especially those with colostomy or ileostomy. • Prepare patient for periodic cystometry to evaluate response to therapy. • Watch geriatric patients for confusion and mental changes. • Be alert for adverse reactions. • Drug may aggravate symptoms of hyperthyroidism, coronary artery disease, heart failure, arrhythmias, tachycardia, hypertension, or prostatic hyperplasia. • Assess patient’s and family’s knowledge of drug therapy. Nursing diagnoses • Acute pain related to bladder spasms • Risk for injury related to drug-induced adverse CNS reactions • Deficient knowledge related to drug therapy. Planning and implementation • If patient has a UTI, give antibiotics. • To minimize tendency toward tolerance, periodically stop therapy to determine whether patient can be weaned off medication. Alert: Don’t confuse Ditropan with diazepam or Dithranol. Patient teaching • Warn patient to avoid hazardous activities until the drug’s CNS effects are known. • Tell patient not to drink alcohol during therapy. • Advise patient that taking drug in hot weather raises the risk of fever or heatstroke, and urge patient to take precautions to avoid excessive heat and maintain adequate hydration. • Instruct patient to change transdermal patch two times per week and avoid using the same site within 7 days. Also warn patient to wear only one patch at a time and to properly dispose of old patches to prevent accidental application or ingestion. • Advise patient to store drug in tightly closed containers at room temperature. Evaluation • Patient is free bladder pain. • Patient sustains no injuries from drug-induced adverse CNS reactions. • Patient and family state understanding of drug therapy. Bethanechol chloride Duvoid, Urecholine Pharmacologic class: cholinergic agonist Therapeutic class: urinary tract stimulant Pregnancy risk category: C Nursing process Assessment • Obtain history of patient’s bladder condition before therapy and reassess regularly throughout therapy. • Be alert for adverse reactions and drug interactions. • Assess patient’s and family’s understanding of drug therapy. Nursing diagnoses • Impaired urinary elimination related to underlying bladder condition • Ineffective breathing pattern related to drug-induced broncho-constriction. • Deficient knowledge related to drug therapy Planning and implementation • Give P.O. drug on empty stomach to prevent nausea and vomiting. Alert: Never give I.V. or I.M. Alert: Always have atropine injection readily available and be prepared to give 0.5mg S.C. or slow I.V. push. Provide respiratory support, p.r.n. Patient teaching • Advise patient to take oral dose on an empty stomach • Tell patient to report breathing difficulty immediately. Evaluation • Patient is able to void without urine retention. • Patient’s respiratory function remains normal during therapy. • Patient and family state understanding of drug therapy. Tolterodine tartrate Detrol, Detrol LA Pharmacologic class: muscarinic receptor antagonist Therapeutic class: Anticholinergic Pregnancy risk category: C Nursing process Assessment • Assess baseline bladder function before starting therapy, and reassess frequently to monitor the drug’s effectiveness. • Be alert for adverse reactions and drug interactions. • Assess patient’s and family’s knowledge of drug therapy. Nursing diagnoses • Impaired urinary elimination related to underlying medical condition. • Urine retention related to drug-induced adverse effects • Deficient knowledge related to drug therapy Planning and implementation • Food increases the absorption of tolterodine, but no dose adjustment is needed. • In the case of urine retention, notify prescriber and prepare for urinary catheterization. • Dry mouth is the most frequently reported adverse reaction. Patient teaching • Tell patient that sugarless gum, hard candy, or saliva substitute may help relieve dry mouth. • Advise patient to avoid during or other potentially hazardous activities until visual effects of drug are known. • Instruct patient to immediately report signs of infection, urine retention, or GI problems. Evaluation • Patient experiences improved bladder function with drug therapy. • Patient doesn’t experience urine retention. • Patient and family state understanding of drug therapy.