P : Caution when used during pregnancy
L : Contraindicated in lactation
||See TERMINOLOGY & ABBREVIATIONS ||
|Indication(s) & Dosage||Chloroquine resistant falciparum malaria acute attack
Adult: Per tab contains pyrimethamine 25 mg orally and sulfadoxine 500 mg: 2-3 tabs orally as a single dose. Do not repeat for at least 7 days.
Child: Pyrimethamine 25mg + Sulfadoxine 500mg (Tablet): <2 yr (5-10 kg): Â½ tab as a single dose; 2-5 yr (>10-20 kg): 1 tab as a single dose; 5-10 yr (< 20-30 kg): 1Â½ tab as a single dose; 10-14 yr (> 30-45 kg): 2 tab as a single dose. Do not repeat for at least 7 days.
Renal impairment: Dose reduction may be needed. Severe: contra-indicated.
Hepatic impairment: Dose reduction may be needed. Severe: contra-indicated.
|Overdosage||Symptoms: Headache, nausea, anorexia, vomiting, CNS stimulation, megaloblastic anaemia, leukopenia, thrombocytopenia, glossitis and crystalluria. Management: Treatment is symptomatic and supportive. Emesis and gastric lavage to reduce drug absorption. Ensure that patient is adequately hydrated to prevent kidney damage. Monitor renal, hepatic, and haematopoietic systems for at least 1 month after overdosage. Folinic acid may be admin for depressed platelet or WBC counts.|
|Contraindications||Severe renal or hepatic impairment, blood dyscrasias, hypersensitivity to components, megaloblastic anaemia due to folate deficiency, pregnancy at term and during lactation, infants â‰¤ 2 mth old.|
|Special Precautions||Impaired renal or hepatic function, folate deficiency, severe allergy or bronchial asthma, G6PD deficiency, pregnancy. Take with plenty of water to prevent crystalluria. Avoid excessive exposure to sun. Discontinue at the first sign of rash. Discontinue if signs of folic acid deficiency develops. Regular CBC monitoring, LFT, analysis of urine for crystalluria when admin for > 3 mth. Take with food to minimise Gi effects (e.g. anorexia and vomiting).|
|Adverse Drug Reaction(s)||Urticaria, serum sickness, photosensitisation, arthralgia, nausea,
vomiting, abdominal pain, diarrhoea, headache, peripheral neuritis, ataxia, tinnitus, vertigo, convulsions, toxic nephrosis and pulmonary infiltrates
resembling eosinophilic or allergic alveolitis.
Potentially Fatal: Stevens-Johnson syndrome, toxic epidermal necrolysis, fulminant hepatic necrosis, blood dyscrasias, anaphylactoid reactions.
|Drug Interactions||Increased halofantrine and
chlorpromazine levels. Increased effects of warfarin.
Potentially Fatal: Increased halofantrine and chlorpromazine levels. Increased effects of warfarin. Please consult manufacturer's PIL (Prescribing Information Leaflet) for detailed drug interactions.
|Pregnancy Category (FDA)||Category C: Either studies in animals have revealed adverse effects on the foetus (teratogenic or embryocidal or other) and there are no controlled studies in women or studies in women and animals are not available. Drugs should be given only if the potential benefit justifies the potential risk to the foetus.|
|Pharmacology||Pyrimethamine, a folic acid antagonist, inhibits the reduction of dihydrofolic acid to tetrahydrofolic acid (folinic
acid). Sulfadoxine, a structural analog of p-aminobenzoic acid (PABA), competitively inhibits dihydrofolic acid synthesis which is important for PABA
conversion to folic acid. This combination results in a synergistic action against susceptible plasmodia. Both have prolonged half-lives enabling single dose
Absorption: Peak plasma concentration: 4 hr.
Distribution: Volume of distribution: 0.14 L/kg (sulfadoxine); 2.3 L/kg (pyrimethamine). Protein binding: 90% (for both drugs). Both drugs cross placenta and passes into breast milk.
Metabolism: Sulfadoxine: 5% appear in blood as acetylated metabolite, 2-3% as glucuronide. Pyrimethamine converted to several metabolites.
Excretion: Elimination half life: 100 hr (pyrimethamine); 200 hr (sulfadoxine). Excreted mainly via kidneys.
|ATC Classification||P01BD01 - pyrimethamine; Belongs to the class of diaminopyrimidine antimalarials.|
Total Products : 4
|Brand Name||Manufacturer/Marketer||Composition||Dosage Form||Pack Size & Price|
|MALACIDE||Square Pharmaceuticals Ltd.||Sulfadoxine 500mg + Pyrimethamine 25mg||Tablet||10x6's: 265.80 MRP|
|MALASON||Hudson Pharmaceuticals Ltd||Sulfadoxine 500mg+ Pyrimethamine 25mg||Tablet||100's: 380.00 MRP|
|MALEX||IBN SINA Pharmaceutical Industry Ltd.||Sulfadoxine 500mg+ Pyrimethamine 25mg||Tablet||30's: 123.00 MRP|
|SULFAMIN||Jayson Pharmaceuticals Ltd.||Sulfadoxine 500mg+ Pyrimethamine 25mg||Tablet||30's: 132.00 MRP|