Gantrisin (sulfisoxazole) is an antibacterial sulfonamide available as a pediatric suspension for oral administration. Each teaspoonful (5 mL) of the pediatric suspension contains the equivalent of approximately 0.5 gm sulfisoxazole in the form of acetyl sulfisoxazole.
Gantrisin (sulfisoxazole) is indicated for the following:
Acute, recurrent or chronic urinary tract infections (primarily pyelonephritis, pyelitis and cystitis) due to susceptible organisms (usually Escherichia coli, Klebsiella-Enterobacter, staphylococcus, Proteus mirabilis and, less frequently, Proteus vulgaris) in the absence of obstructive uropathy or foreign bodies.
Meningococcal meningitis where the organism has been demonstrated to be susceptible. Haemophilus influenzae meningitis as adjunctive therapy with parenteral streptomycin.
Meningococcal meningitis prophylaxis when sulfonamide-sensitive group A strains are known to prevail in family groups or larger closed populations. (The prophylactic usefulness of sulfonamides when group B or C infections are prevalent has not been proven and in closed population groups may be harmful.)
Acute otitis media due to Haemophilus influenzae when used concomitantly with adequate doses of penicillin or erythromycin (see appropriate labeling for prescribing information).
Trachoma. Inclusion conjunctivitis. Nocardiosis. Chancroid. Toxoplasmosis as adjunctive therapy with pyrimethamine. Malaria due to chloroquine-resistant strains of Plasmodium falciparum, when used as adjunctive therapy.
Currently, the increasing frequency of resistant organisms is a limitation of the usefulness of antibacterial agents including the sulfonamides, especially in the treatment of chronic and recurrent urinary tract infections.
Important Note: In vitro sulfonamide susceptibility tests are not always reliable. The test must be carefully coordinated with bacteriologic and clinical response. When the patient is already taking sulfonamides, follow-up cultures should have aminobenzoic acid added to the culture media.