Sulfadiazine is a short-acting sulphonamide with bacteriostatic activity against a broad spectrum of organisms.
Gram-positive – particularly group A Streptococci and some strains of Streptococcus pneumoniae, Bacillus ant hracis, Nocardia (especially N.asteroides) and, to a lesser extent, Staphylococci and Clostridium perfringens.
Gram-negative – Haemophilus influenzae and H.ducreyi are often sensitive, sensitivity varies among the enterobacteriae-Escherichia coli, Klebsiella, proteus, Salmonella and Serratia and Vibrio cholerae are sometimes sensitive. Other organisms reported to be sensitive include, Actinomyces spP., Brucella, Calymmatobacterium granulomatis, Legionella, Yersinia pestis, Chlamydia, Pseudomonas pseudomallei.
Adults and elderly
The initial dose is usually 2-4 grams followed by a maintenance dose of up to 4 grams daily in divided doses for a maximum of seven days.
Dosage reduction may be necessary in renal impairment.
Initially 75mg/kg, followed by a maintenance dose of 150mg/kg daily in divided doses. Maximum of 6 grams daily.
Sulphonamides should not be used for initial treatment of meningococcal meningitis although oral Sulfadiazine may be substituted for parenteral penicillin once susceptibility to sulphonamides has been established.
Thyroid fuction disturbance
Frequency Not Defined
Sstevens Johnson syndrome