Category:

• Antibiotic

Description:

• Sulfonamide antibiotic

Indications:

• Chancroid

• Inclusion conjunctivitis

• Malaria (adjunctive therapy)

• Meningitis (H. influenzae and meninogococcal)

• Nocardiosis

• Toxoplasmosis

• Trachoma

• Urinary tract infections (pyelonephritis, cystitis)

• Lymphogranuloma venereum (alternative to doxycycline)

• Chlamydia trachomatic infections (alternative to doxycycline and azithromycin)  

Contraindications:

• Hypersensitivity to sulfa-related medications (sulfonylureas, thiazide and loop diuretics, carbonic anhydrase inhibitors, sunscreens with PABA, local anesthetics)

• Pregnancy at term

• Lactation

• Infants less than 2 months old (except congenital toxoplasmosis as adjunct with pyrimethamine)

Precautions:

• Pregnancy category C

• Sulfonamides have been associated with severe hypersensitivity reactions and death.

• Serious blood disorders (agranulocytosis, hepatocellular necrosis, aplastic anemia) have been associated with sulfonamides.  Perform complete blood counts.  Symptoms of sore throat, fever, pallor, purpura or jaundice may be early signs of serious blood disorders.

• Use with caution in patients with severe asthma or allergies.

• Hemolytic anemia may occur in patients with G-6-PD deficiency.

• Photosensitization may occur, caution patients to use protective measures against ultraviolet or sunlight until tolerance is determined.

• Sulfonamides increase the effect of oral anticoagulants (warfarin).

• Take with a full glass of water and increase fluid intake to 2-3 liters per day.

• Complete full course of therapy.

Adverse Reactions (Side Effects):

• Headache, peripheral neuropathy, depression

• Tinnitis, vertigo

• Nausea, emesis, abdominal pain, anorexia, diarrhea

• Hepatitis, pancreatitis, stomatitis

• Urticaria, Stevens-Johnson type erythema multiforme

• Crystalluria, elevated creatinine

• Drug fever, chills

• Photosensitivity

Dosage:

Administered orally (tablets)

• Adults:

  • Loading dose: 2-4 grams

  • Maintenance dose: 2-4 grams per day in 3-6 divided doses

• Children (>2 months):

  • Initial dose: 75mg/kg

  • Maintenance dose: 150mg/kg/day in 4-6 divided doses (maximum of 6 grams per day)

• Toxoplasmosis:

  • treat for 3-4 weeks

  • Infants (<2 months): 25mg/kg/dose qid

  • Children (>2 months): 25-50mg/kg/dose qid

• Recurrent attacks of rheumatic fever:

  • Patients > 30kg: 1 gram per day

  • Patients < 30kg: 500mg per day