Sulfadiazine + Trimethoprim

Generic Medicine Info
Indications and Dosage
Urinary tract infections
Adult: Per tablet contains sulfadiazine 410 mg and trimethoprim 90 mg or per 5 mL suspension contains sulfadiazine 205 mg and trimethoprim 45 mg: 2 tablets or 20 mL as a single dose every 24 hr.
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.
Hypersensitivity; severe renal/hepatic impairment; blood dyscrasias, porphyrias, serious hematological disorders; megaloblastic anemia secondary to folate depletion. Infants ≤2 mth; pregnancy (at term), lactation.
Special Precautions
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.
Adverse Reactions
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.
Drug Interactions
Sulphadiazine: Potentiates antidiabetic effect of sulphonylureas. Action antagonised by para-aminobenzoinc acid and procaine group of local anaesthetics.
Trimethoprim: Potentiate effects of phenytoin, digoxin, procainamide, warfarin. Reduces renal excretion of zalcitabine, zidovudine and lamivudine. Dapsone; rifampicin; increase risk of nephrotoxicity when given with cyclosporin; severe hyperkalaemia when given with ACE inhibitor; depressants of bone marrow function; risk of megaloblastic anemia with other folate inhibitors eg pyrimethamine, methotrexate; hyponatraemia if receiving diuretics concurrently.
Potentially Fatal: Potentiates oral anticoagulants, methotrexate and phenytoin. Ascorbic acid and hexamine may precipitate crystalluria; metabolism of oral hypoglycaemics may be inhibited.
Food Interaction
Avoid vit C or acidifying agents to prevent crystalluria.
Lab Interference
Interferes with estimation of urinary glucose, urobilinogen, urea and creatinine. May interfere with serum methotrexate assay where dihydrofolate reductase is used. Jaffe reaction for creatinine.
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.
MIMS Class
Antibacterial Combinations
Disclaimer: This information is independently developed by MIMS based on Sulfadiazine + Trimethoprim from various references and is provided for your reference only. Therapeutic uses, prescribing information and product availability may vary between countries. Please refer to MIMS Product Monographs for specific and locally approved prescribing information. Although great effort has been made to ensure content accuracy, MIMS shall not be held responsible or liable for any claims or damages arising from the use or misuse of the information contained herein, its contents or omissions, or otherwise. Copyright © 2023 MIMS. All rights reserved. Powered by
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