NURS 133 Sulfonamides and Trimethoprim-Sulfamethoxazole

jasmine's version from 2016-05-22 00:48

Section 1

Question Answer
Sulfonamides Commonly referred to as sulfa drugs; Anti-microbials that disrupt the synthesis of tetrahydrofolic acid
Sulfonamide actions Suppress bacterial growth by inhibiting synthesis of folic acid (folate), a compound required by all cells to make DNA, RNA, and proteins; Block the step in which PABA is combined with pteridine to form dihydropteroic acid; due to their structural similarity to PABA, sulfonamides act as competitive inhibitors of this reaction; Sulfonamides are usually bacteriostatic; host defenses are essential for complete elimination of infection
Sulfonamide therapeutic uses Urinary tract infection
Elimination/Excretion of Sulfonamides Metabolized in the liver by acetylation (N-acetylation), and excreted by the kidney through glomerular filtration (metabolites are insoluble in urine, hence crystalluria can occur)
Adverse/Side Effects of Sulfonamides Hypersensitivity; hepatitis, bone marrow depression and crystalluria; Produce kenicterus (bilirubin-induced brain dysfunction) in neonates due to the displacement of bilirubin form serum albumin binding site; Can cause hemolytic aplastic anemia with glucose-6-phosphate dehydrogenase deficiency; nausea, vomiting headache and mental depression; Rashes, fever, eosinophilia
Contraindications of Sulfonamides Hypersensitivity; Contraindicated in patients who have porphyria (a rare hereditary disease in which the blood pigment hemoglobin is abnormally metabolized. Porphyrins are excreted in the urine, which becomes dark; other symptoms include mental disturbances and extreme sensitivity of the skin to light); Can cause hemolytic anemia in patients whose red blood cells have a genetically determined deficiency in glucose-6-phosphate dehydrogenase (G6PD); Kernicterus: Sulfonamides promote kernicterus by displacing bilirubin from plasma proteins. Since the blood-brain barrier of infants is poorly developed, the newly freed bilirubin has easy access to sites within the brain. Sulfonamides should not be administered to infants under the age of 2 months. In addition, should not be given to pregnant women near term or to mothers who are breast-feeding. Renal damage from crystalluria; Due to low solubility, older sulfonamides tend to come out of solution in the urine, forming crystalline aggregates in the kidneys, ureters, and bladder. These aggregates caused irritation and obstruction, sometimes resulting in anuria and even death. Renal damage is uncommon with today’s sulfonamides, owing to their increased water solubility. However to minimize the risk, adults should maintain a daily urine output of 1200 mL. Should not be used to treat group A streptococcal pharyngitis due to sulfonamides do not eradicate group A streptococci in patients with pharyngitis.
Drug/Food interactions of Sulfonamides Can intensify the effects of warfarin, phyenytoin, and sulfonylurea-type oral hypoglycemics (glipizide, glyburide); The principle mechanism is inhibition of hepatic metabolism; Cross-hypersensitivity (e.g., thiazide diuretics, loop diuretics, sulfonylurea-type oral hypoglycemics). However, no good data to show cross-hypersensitivity exists. Either way, Patients who are allergic to sulfonamide antibiotics should avoid all other sulfonamide-type drugs. Among the drugs that may interact by change or risk of side effects may include: Acetaminophen, medicine for overactive thyroid, androgens, estrogens, birth control pills, other medicines used to treat infections, medicines for diabetes such as glyburibe, blood thinners such as warfarin, disulfiram used to treat alcohol abuse, amantadine used to treat flu and also parkinson’s disease, diuretics such as hydrochlorothiazide, anti-cancer drug such as methotrexate, anti-seizure medicines such as valproic acid (
Medication administration of Sulfonamides PO and IV
Nursing interventions of Sulfonamides Red blood cell count should be assessed due to the possibility of drug-related anemias with sulfonamides; monitor for renal toxicity, as renal toxicity is an adverse effect of sulfonamides; Assess for fever, rash, blistering, and resulting drying and shedding of skin (stevens Johnson syndrome is common in sulfonamide therapy)
Client education of Sulfonamides Advise patient to avoid driving and activities that require alertness, as drug may cause dizziness; may cause blood problems that can interfere with healing and lead to additional infections, so injuries should be avoided; especially important advise patient also not to damage mouth when brushing or flossing teeth-dental work should not be one until blood is back to normal; inform patient the drug may increase sensitivity to sunlight, and can cause sunburn or rash-should avoid direct sunlight and wear protective clothing. Babies under 2 months should not be given sulfonamides; other people may be especially sensitive to effects of drug (; Instruct patients to complete the prescribed course of treatment; Advise patients to take oral sulfonamides on an empty stomach and with a full glass of water; Instruct patient to contact health care professional for any unusual or severe adverse/side effects (e.g., itching or skin rash, reddish or purplish spots on skin, other skin problems, such as redness, blistering, peeling, severe, watery or bloody diarrhea, muscle or joint aches, fever, sore throat, cough, shortness of breath, unusual tiredness or weakness, unusual bleeding or bruising, paleskin, yellow eyes or skin, swallowing problems
Evaluation/Desired outcomes of Sulfonamides Trimethoprim/Sulfamethoxazole: Resolution of the signs and symptoms of infection. Length of time for complete resolution depends on organism and site of infection; Resolution of symptoms of traveler’s diarrhea; Prevention of pneumocystis jirovecii pneumonia in patients with HIV. Zonisamide: Decrease in frequency and duration of partial seizures

Section 2

Question Answer
Trimethoprim/Sulfamethoxazole An antibiotic that kills sensitive bacteria. Most widely used. Also known as cotrimoxazole is a combination of two anti-microbial agents that act synergistically against a wide variety of bacteria; Used with sulfamethoxazole
Trimethoprim actions Combination inhibits the metabolism of folic acid in bacteria at two different points
Trimethoprim therapeutic usesUsed to treat infections such as urinary tract infections, middle ear infections (otitis media), bronchitis, traveler's diarrhea, and shigellosis (bacillary dysentery). This medicine is also used to prevent or treat Pneumocystis jiroveci pneumonia or Pneumocystis carinii pneumonia (PCP), a very serious kind of pneumonia. This type of pneumonia occurs more commonly in patients whose immune systems are not working normally, such as cancer patients, transplant patients, and patients with acquired immune deficiency syndrome (AIDS). Sulfamethoxazole and trimethoprim combination is an antibiotic. It works by eliminating the bacteria that cause many kinds of infections. This medicine will not work for colds, flu, or other virus infections; Bactericidal action against susceptible bacteria; Active against many strains of gram-positive aerobic pathogens; Has activity against many aerobic gram-negative pathogens
Elimination/Excretion of Trimethoprim Some metabolism by the liver (20 percent); remainder excreted unchanged by the kidneys
Adverse/Side Effects of Trimethoprim Pseudomembranous colitis, hepatic necrosis, nausea, vomiting, erythema multiforme, Stevens Johnson syndrome, toxic epidermal necrolysis, rash, agranulocytosis, aplastic anemia, phlebitis
Contraindications of Trimethoprim Hypersensitivity to sulfonamides or trimethoprim; history of drug-induced immune thrombocytopenia due to sulfonamides or trimethoprim; megaloblastic anemia secondary to folate deficiency, severe hepatic or renal impairment; OB, Lactation, Pedi: pregnancy, lactation, or children < 2 mo (can cause kernicterus in neonates); Exception: neonates born to HIV-infected mothers (prophylaxis should be initiated at 4-6 weeks of age)
Drug/Food interactions of Trimethoprim May increase half-life, decrease clearance, and exaggerate folic acid deficiency caused by phenytoin. May increase effects of sulfonylureas, pioglitazone, rosiglitazone, repaglinide, phenytoin, digoxin, and warfarin. May increase toxicity of methotrexate. May increase risk of thrombocytopenia from thiazide diuretics (increase in geriatric patients). Decrease levels of and increase risk of nephrotoxicity with cyclosporine. Concurrent use with ACE inhibitors may increase risk of hyperkalemia. May decrease the effects of tricyclic anti-depressants. Concurrent use with leucovorin may result in treatment failure and increase risk of death (avoid concurrent use)
Medication administration of Trimethoprim PO and IV
Nursing interventions of Trimethoprim Assess for infection at beginning of and during therapy; Obtain specimens for culture and sensitivity before initiating therapy; Inspect IV site frequently, as phlebitis is common; Assess patient for allergy to sulfonamides; monitor intake and output ratios; monitor bowel function. Diarrhea, abdominal cramping, fever, and bloody stools should be reported to health care professional promptly as a sign of pseudomembranous colitis. May begin up to several weeks following cessation of therapy. Assess for rash periodically during therapy. May cause Steven Johnson syndrome. Discontinue therapy if severe or if accompanied with fever, general malaise, fatigue, muscle or joint aches, blisters, oral lesions, conjunctivitis, hepatitis and/or eosinophilia; Lab test considerations: monitor CBC and urinalysis periodically during therapy. May produce increase serum bilirubin, increase potassium, creatinine, and alkaline phosphatase; may cause hypoglycemia
Client education of Trimethoprim Instruct patient to take medication around clock and to finish drug completely as directed; Instruct patient to notify health care professional if rash, or fever and diarrhea develop, especially if diarrhea contains blood, mucus, or pus; Advise patient not to treat diarrhea without consulting health care professional; Caution patient to use sunscreen and protective clothing; Advise patient to notify health care professional if skin rash, sore throat, fever, mouth sores, or unusual bleeding or bruising occurs; Instruct patient to notify health care professional if symptoms do not improve within a few days; Emphasize importance of regular follow up exams to monitor blood counts in patients on prolonged therapy; Home care issues: Instruct family or caregiver on dilution, rate, and administration of drug and proper care of IV equipment
Evaluation/Desired outcomes of Trimethoprim Resolution of the signs and symptoms of infection; Length of time for complete resolution depends on organism and site of infection; Resolution of symptoms of traveler’s diarrhea; Prevention of pneumocystis jirovecii pneumonia in patients with HIV
Potential nursing diagnoses of Trimethoprim/sulfamethoxazole Risk for infection (indications/side effects); Non-compliance (patient/family teaching)