Sulfamerazine

Oral
Susceptible infections

Dose reduction may be needed.

Dose reduction may be needed.

Severe renal or hepatic failure; blood disorders; hypersensitivity to sulfonamides; acute porphyria; SLE. Pregnancy and lactation; infants ≤2 mth.

Renal or hepatic impairment; history of allergy or asthma; AIDS; G6PD deficiency (at risk of hemolytic reactions); elderly; ensure adequate fluid intake to reduce risk of crystalluria. Discontinue use if rash develops.

Nausea, vomiting, anorexia, diarrhoea, hypersensitivity reactions, SLE, serum sickness-like syndrome, liver necrosis and hepatomegaly, myocarditis, pulmonary eosinophilia and fibrosing alveolitis, vasculitis, hypoglycaemia, hypothyroidism, neurological reactions, jaundice and kernicterus in premature neonates. Pseudomembranous colitis.
Potentially Fatal: Blood dyscrasias, Stevens-Johnson Syndrome, toxic epidermal necrolysis, anaphylaxis.

Potentiates effects of oral anticoagulants, methotrexate, phenytoin. Increased risk of crystalluria by compounds that render the urine acidic.

Interference with tests for urea, creatinine, urinary glucose and urobilinogen.

Description:
Mechanism of Action: Sulfamerazine is a short-acting sulfonamide that interferes with the synthesis of nucleic acids in sensitive organisms by blocking the conversion of p-aminobenzoic acid (PABA) to the co-enzyme dihydrofolic acid. Its action is bacteriostatic, bactericidal effect may be exerted where concentrations of thymine are low in the surrounding medium. It is usually administered with other sulfonamides or with trimethoprim.

Sulphonamid