Description
Sulphadiazine is a short-acting sulphonamide derivative with bacteriostatic action through competitive inhibition of bacterial synthesis of folic acid. Trimethoprim inhibits enzymes folic acid pathway, preventing the reaction of the dihydrolic acid to tetrahydrofolate.
Indications
Indicated in Urinary tract infections
Contraindications
Hypersensitivity; severe renal/hepatic impairment; blood dyscrasias, porphyrias, serious hematological disorders; megaloblastic anemia secondary to folate depletion. Infants ≤2 mth; pregnancy (at term), lactation.
Adverse Effects
Nausea, vomiting, anorexia and diarrhoea. Hypersensitivity, skin reactions; lumbar pain, haematuria, oliguria, anuria, crystallisation in urine, thrombocytopaenia, leucopaenia, eosinophilia, neonatal jaundice and kernicterus.
Potentially Fatal: Stevens-Johnson syndrome; agranulocytosis, thrombocytopaenia, jaundice in new born. Mild GI disturbances; pruritus; skin rash; sulfonamide-like skin reactions; disturbances of liver enzyme values, cholestatic jaundice; raised serum creatinine and BUN; fever; anaphylaxis; aseptic meningitis; hematologic disturbances; photosensitivity; induce hyperkalemia particularly in HIV patients being treated for Pneumocystis carinii pneumonia or in the elderly.
Warnings
Elderly, adequate fluid intake, G6PD deficiency, AIDS; actual or possible folate deficiency, child with fragile X chromosome associated with mental retardation; discontinue in case of skin rash; perform regular hematological examination.
Maximum Dosage
Oral
Urinary tract infections
Child: >3 mth: Per day: 14 mg sulfadiazine/kg+3 mg trimethoprim/kg. Daily dose is divided into 2 equal doses given every 12 hr.
How supplied
Sulfadiazine / Trimethoprim
Tablets
- Sulphadiazine 800 mg, Trimethoprim 160 mg
- Sulphadiazine 400 mg, Trimethoprim 80 mg
Suspension
- Sulphadiazine 200 mg/5ml, Trimethoprim 40 mg/5ml