Generic
Pyrimethamine + Sulfadoxine
4 brands available in the market
At a glance
Pyrimethamine + Sulfadoxine is a combination medicine used for the treatment of malaria. Pyrimethamine is an antiparasitic that increases haeme levels toxic to the malaria parasite, and Sulfadoxine is an antibiotic that stops bacterial folic acid production.
Description
Pyrimethamine is a folic acid antagonist that inhibits parasitic dihydrofolate reductase, preventing tetrahydrofolic acid synthesis. Sulfadoxine is a sulfonamide antibiotic that inhibits dihydropteroate synthetase by competing with para-aminobenzoic acid, preventing bacterial folic acid production. This combination provides synergistic effects against malaria parasites.
Indications
- Malaria
Therapeutic class
Anti-malarial drugs
Pharmacological class
Folic Acid Antagonist + Sulfonamide
Pharmacology
Pyrimethamine inhibits parasitic dihydrofolate reductase, preventing tetrahydrofolic acid synthesis. Sulfadoxine inhibits dihydropteroate synthetase by competing with para-aminobenzoic acid, preventing folic acid production. This combination provides synergistic effects against malaria parasites.
Mechanism of action
Prevents malaria infection by inhibiting the parasite's folic acid metabolism.
Dosage
Adult Dose (Oral):
- Malaria: 3 tablets (each containing 25 mg pyrimethamine + 500 mg sulfadoxine) as a single dose
Administration
- Take with food
- Swallow tablet whole; do not chew, crush, or break
- Take at the same time each day
Missed dose
If you miss a dose, take it as soon as you remember; skip if it's almost time for next dose; do not double the dose.
Side effects
Common Side Effects:
- Nausea
- Vomiting
- Diarrhea
- Fatigue
- Feeling of fullness
- Dizziness
- Headache
- Mouth sore
- Skin rash
Precautions & warnings
- May affect driving ability; do not drive if dizzy or drowsy
- Avoid alcohol (excessive drowsiness)
- Caution in kidney and liver disease
- Caution in pregnancy and lactation
Contraindications
- Hypersensitivity to pyrimethamine, sulfadoxine, or sulfonamides
- Severe liver or kidney disease
- Pregnancy and lactation
Drug interactions
- Other sulfonamides: Additive adverse effects
- Folic acid antagonists: Additive effects
Food interactions
Caution is advised when consuming alcohol with Pyrimethamine + Sulfadoxine.
Use in pregnancy
Use in Pregnancy: May be unsafe during pregnancy; animal studies have shown harmful effects; consult your doctor.
Pregnancy Category: D — always consult a doctor before taking during pregnancy.
Use in lactation
Use in Lactation: Probably unsafe; limited human data suggests drug may pass into breast milk; caution required.
Pediatric use
Pediatric dose based on age and weight; consult your doctor.
Geriatric use
Caution required in elderly patients; dose adjustment may be needed.
Renal / hepatic impairment
Renal Impairment: Caution in kidney disease; dose adjustment may be needed; consult your doctor.
Hepatic Impairment: Caution in liver disease; dose adjustment may be needed; consult your doctor.
Overdose effects
Overdose: Nausea, vomiting, headache, skin reactions, blood dyscrasias; treatment: symptomatic supportive care, gastric lavage.
Storage conditions
Store in a cool and dry place, away from light; keep out of reach of children.
Chemical structure
Pyrimethamine + Sulfadoxine