Chapter 31 Sulfonamides
When teaching a patient about trimethoprim-sulfamethoxazole (TMP-SMZ), the nurse gives highest priority to teaching the patient to A) increase fluid intake. B) report signs of ringing in the ears or loss of hearing. C) expect the color of their urine to change to a reddish orange. D) take this drug with dairy products or antacids to protect the stomach.
Answer A Rationale: Fluid intake should be increased to at least 2000 mL/day when taking sulfonamides to prevent crystalluria. Ototoxicity is not a common adverse effect of sulfonamides. The urine will not change colors. Dairy products or antacids should not be taken at the same time as sulfonamides because they decrease absorption.
Sulfasalazine (Azulfidine) is ordered for a patient. This medication is most often used to treat A) fungal infections. B) ulcerative colitis. C) yeast infections. D) skin infections.
Answer B Rationale: Sulfasalazine (Azulfidine) is used for the treatment of ulcerative colitis, Crohn's disease, rheumatoid arthritis. It is also used to reduce Clostridium and E. coli in stools.
A patient is ordered to receive co-trimoxazol/TMP-SMZ (Bactrim). This medication is a combination of two medications that are A) antagonistic. B) additive. C) synergistic. D) contraindicated.
Answer C Rationale: A synergistic effect results in increasing the desired drug response.
After taking a sulfonamide, a patient develops desquamation, scaling, and itching of skin. The nurse identifies this condition as A) Stevens-Johnson syndrome. B) contact dermatitis. C) exfoliative dermatitis. D) erythema multiforme.
Answer C Rationale: Exfoliative dermatitis (desquamation, scaling, and itching of skin) is an adverse reaction to sulfonamide therapy. Erythema multiforme (erythematous macular, papular, or vesicular eruption), if severe, can cover the entire body. Stevens-Johnson syndrome is characterized by lesions and ulcers in the mucous membranes. A rash of round lesions can arise on the face, trunk, arms, legs, and scalp.
Which statement about sulfonamide therapy is true? A) When used with sulfonylureas, sulfonamides decrease the hypoglycemic effect. B) When sulfonamides are used with warfarin, the anticoagulant effect is decreased. C) Sulfonamides must be taken with antacids to prevent gastric ulceration. D) Patients on sulfonamide therapy need to increase their fluid intake.
Answer D Rationale: Patients taking sulfonamides need to drink several quarts of fluid daily to avoid the complication of crystalluria. These drugs increase the hypoglycemic effect of sulfonylureas, increase the anticoagulant effect of warfarin, and should not be taken with antacids because antacids decrease the absorption rate of the drug.
A patient has been prescribed trimethoprim-sulfamethoxazole (TMP-SMZ). The nurse realizes that this drug is most likely used to treat which condition? A) Gonorrhea B) Rickettsial infection C) Chlamydial infection D) Urinary tract infection
Answer D Rationale: TMP-SMZ is used to treat urinary tract infections, otitis media, bronchitis, pneumonia, rheumatic fever, and burns. It does not treat gonorrhea, rickettsial or chlamydial infections.
What are the side effects and adverse reactions of Sulfonamides?
GI distress, stomatitis, photosensitivity, crystalluria, renal failure, blood dyscrasis, and Stevens-Johnson syndrome
What are the adverse reactions of Trimethoprim-Sulfamethoxazole (Bactrim)?
Life-threatening: SEIZURES, leukopenia, thrombocytopenia, increased bone marrow depression, hemolytic anemia, aplastic anemia, agranulocytosis, angioedema, hyperkalemia, hyponatremia, hypoglycemia, crystalluria, PSEUDOMEMBRANOUS COLITIS, STEVENS-JOHNSON SYNDROME, RENAL FAILURE
cystitis
an infection in any part of the urinary system, the kidneys, urethra, or bladder
What are the side effects of Triamethoprim-Sulfamethoxazole (Bactrim)?
anorexia, nausea, vomiting, diarrhea, abdominal pain, rash, STOMATITIS, fatigue, depression, VERTIGO, insomnia, and PHOTOSENSITIVITY
cross-sensitivity
a sensitivity or allergy to one sulfunamide may lead to a sensitivity to another sulfunamide (or with any drug)
synergistic effect
combined action of drugs is greater than drugs independently -ex: Triamethoprim and Sulfamethoxazole together causes bacterial resistance to develop much more slowly than if only one of the drugs is used alone
crysalluria
crystals in urine
photosensitvity
excessive reaction to direct sunlight or ultraviolet light leading to redness and burning of the skin
Administer sulfonamides with a...
full glass of water
What are the major drug-lab-food interactions with Trimethoprim-Sulfamethoxazole (Bactrim)?
increases anticoagulant effect with warfarin (treats blood clots), increase potassium with ACE inhibitors, increase digoxin (treats heart failure and heart rhythm problems) levels, increase phenytoin and methotrexate toxicity; Lab-may increase BUN and serum creatine
What is the action of Sulfonamides?
inhibit bacterial synthesis of folic acid, bacteriostatic drug, and fights gram-negative bacteria
What are Sulfonamides used for?
otitis media, respiratory infections, UTIs, prostatitis, gonorrhea, meningococcal meningitis, and alternative therapy for pts allergic to penicllin
What is Mafenide acetate (Sulfamylon) used for?
prevents sepsis in cases of second and third degree burns
What are the contraindications of TMP-SMZ or Bactrim?
severe renal or hepatic disease, hypersensitivity to sulfonamides, megaloblastic or folate-deficiency anemia, pregnancy, breastfeeding, infants Caution: malnutrition, hypothyroidism, older adults
What are the symptoms of superinfection?
stomatitis (mouth ulcers), furry black tongue, anal or genital discharge, and itching
Advise pregnant patients to avoid sulfonamides during...
the last 3 months of pregnancy
What are the uses of Trimethoprim-Sulfamethoxazole (TMP-SMZ) or Bactrim?
to treat UTI, otitis media, bronchitis, Streptococcus pnuemoniae, Pneumocystis carinii (common in pts with AIDS), Klebsiella, Escherichia coli, and cystitis
What is silver sulfadiazine (Silvadene) used for?
treatment of burns