Antibiotic (Sulfonamide)
Last reviewed June 2026
Who is this for?
Sulfadiazine is an antibiotic that works by stopping bacteria from making folic acid, which they need to grow and multiply — this helps your body fight off the infection.
Inhibits bacterial dihydropteroate synthase, blocking the synthesis of dihydrofolate and subsequently tetrahydrofolate, which are essential cofactors for bacterial nucleotide synthesis and DNA replication.
Prescription Required
You need a doctor's prescription to buy this drug.
Explore this drug
Adults usually take 2 to 4 grams (loading dose) to start, then 1 gram every 4 to 6 hours depending on the infection. Drink plenty of water — at least 8 glasses a day — to protect your kidneys while on this drug. You can take it with or without food, but take it at regular intervals as your doctor prescribes.
If you miss a dose, take it as soon as you remember. But if it is almost time for your next dose, skip the missed one and continue your normal schedule. Do not double up to make up for the missed dose.
Important for antibiotics
Always complete the full course even if you feel better. Stopping early can cause the infection to return and become drug-resistant.
Always complete the full course of this antibiotic even if you feel better — stopping early can make the infection come back stronger. Drink plenty of water throughout the day to prevent kidney crystals, which is a known risk with this drug. Only use sulfadiazine when prescribed by a doctor — do not buy from roadside sellers or share with others, as the wrong dose can cause serious harm.
Sulfadiazine can increase the blood-thinning effect of warfarin, raising your risk of bleeding. It may increase the effects of methotrexate, making side effects worse. If you are taking phenytoin (for seizures/convulsion), sulfadiazine can raise its levels in your blood — tell your doctor about all your medications.
Check your specific combination
Is it safe to take Sulfadiazine with your other drugs?
Sulfadiazine is not safe in late pregnancy (especially near delivery) as it can cause serious problems in the newborn, and it passes into breast milk — consult your doctor before using if you are pregnant or breastfeeding.
Store in a cool, dry place away from direct sunlight and heat — Nigerian weather can be very hot, so don't leave it on a windowsill or in a hot car. Keep the container tightly closed to protect from humidity, and always keep out of reach of children.
For information only — not medical advice. Always talk to a doctor or pharmacist before changing your medication.
Names this drug is sold under — especially in Nigerian and West African pharmacies
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Counterfeit Drug Warning
Fake drugs are a serious problem in Nigeria. Always buy from a registered pharmacy. If the packaging looks different from what is described above, do not use it.
Dispensing Sulfadiazine?
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