DUPRIDOX® 525MG TABLETS
(500MG SULFADOXINE + 25MG PYRIMETHAMINE)
COMPOSITION
Each tablet of Dupridox® contains 500mg Sulfadoxine and 25mg Pyrimethamine.
CLINICAL PHARMACOLOGY
Pharmacodynamic Properties
Dupridox® acts on the asexual intraerythrocytic forms of human malaria parasites. Sulfadoxine 
interferes with the bacterial folic acid synthesis and growth via competitive inhibition of para-aminobenzoic acid; pyrimethamine inhibits microbial dihydrofolate reductase, resulting in inhibition of tetrahydrofolic acid synthesis.
Pharmacokinetics Properties
Dupridox® tablets is well absorbed, Sulfadoxine is well distributed like other sulphonamide and pyrimethamine widely distributed mainly in blood cells, kidneys, lungs, liver and spleen. A relatively long elimination half-life is characteristic of both components. The mean values are about 100 hours for pyrimethamine and about 200 hours for sulfadoxine. Both sulfadoxine and pyrimethamine are eliminated mainly via the kidneys.
INDICATIONS
Dupridox® is indicated for the treatment of all forms of malaria due to Plasmodium falciparum, plasmodium vivax, plasmodium ovale and plasmodium malariae. Dupridox® should also be used for the intermittent preventive treatment of malaris in second and third trimester of pregnancy.
CONTRAINDICATIONS
Hypersensitivity to any sulfa drug, pyrimethamine, or any component of the formulation: porphyria, megaloblastic anemia, severe renal insufficiency, children less than two months of age due to competition with billirubin for protein binding sites. Avoid the use of Dupridox in the first trimester and last one month of pregnancy.
DRUG INTERACTIONS
Concurrent administration of other preparations containing folate antagonist (e.g trimethoprim, co-trimoxazole, methotrexate, anticonvulsants) can result in increased impairment of folic acid metabolism which leads to haematological side-effects. There is reported increase of adverse reactions when chloroquine is used with Dupridox® as compared to the use of Dupridox® alone.
WARNINGS
Pregnancy
In pregnant women, limited prophylactic and therapeutic use of sulfadoxine-pyrimethamine did not indicate a risk of foetal damage. Nevertheless, sulfadoxine should be use in pregnancy only if it is absolutely essential, and only after the expected benefit has been weighed against the potential risk to the foetus.
Lactation
Both pyrimethamine and sulfadoxine are secreted in maternal breast milk. Nursing mother should not take sulfadoxine-pyrimethamine. In cases where the use of sulfadoxine-pyrimethamine is essential, women should abstain from breast milk feeding.
PRECAUTIONS
Excessive exposure to the sun must be strictly avoided. Sulfadoxine-pyrimethamine should be discontinued if skin rashes appear. For adequate urinary output, oral intake of fluid should be increased. Use with caution in patients with known renal impairment and/or severe hepatic damage.
ADVERSE EFFECTS
Skin Reactions
Drug rash, pruritus, urticaria, photosensitization and slight hair loss have been observed. These reactions are usually mild and regress spontaneously upon withdrawal of the drug.
Gastro-intestinal Reactions
Feeling of fullness, nausea, rarely vomiting, diarhoea, and stomatitis.
Haematological Changes
In rare cases, leucopenia, thrombocytopenia and megaloblastic anemia have been observed, though these usually have been asymptomatic.
SYMPTOMS OF OVERDOSAGE AND ANTIDOTE
Possible symptoms of over dosage include headache, anorexia, nausea, vomiting, signs of excitation and possibly convulsions and haematological changes (megaloblastic anemia, leucopenia, thrombocytopenia). In acute intoxication, induction of vomiting or gastric lavage as appropriate, as well as fluid replacement is recommended. Possible convulsion due to the pyrimethamine component should be watched for and may require anticonvulsant therapy with parenteral diazepam or a barbiturate.
Monitoring of renal and hepatic function and repeated blood counts is recommended for up to four weeks after overdosage.
If haematological changes are found, folinic acid should be administered intramuscularly.
DOSAGE AND ADMINISTRATION
(a) Intermittent preventive treatment of malaria in pregnancy. One full treatment dose (3 tablets of Dupridox) during the second and third trimesters. The last dose should be given not later than one month before the expected date of delivery.
Note: Second trimester starts from sixteen weeks or when the pregnant woman notices the kicking of the baby.
(b)
| DOSAGE | CURATIVE TREATMENT |
| Adults | 3 tablet – As a single dose |
| Children 9 – 12years | 2 tablets – As a single dose |
| 4 – 8 years | 1 tablet – As a single dose |
Caution: Dupridox® should be taken only in the doses recommended above.
Dupridox® must not be used in the first trimester of pregnancy.
PRESENTATION Drupridox® is available as 500mg sulfadoxine + 25mg pyrimethamine in a strip of 3’s.
STORAGE
Store below 30oC in a cool dry place below. Protect from light.