Composition
Each capsule contains Chloroquine phosphate 250mg:
 

Description
Capquin is an antimalarial product belonging to the group of 4-aminoquinoline. It is a rapidly acting schizonticide, well tolerated and safe. The product is packed in capsules to mask the bitter taste of the product.

Pharmacology

Mircobiology: Capquin has been found to be highly active against the erythrocytic forms of Plasmodium vivax and malariae and most strains of Plasmodium falciparum. The precise mechanism of action of the drug is unknown. While the drug can inhibit certain enzymes, its effect is believed to result from its interaction with DNA. It appears that it acts against the blood schizonts by influencing haemoglobin digestion by the malarial parasites. Capquin also possesses amoebicidal activity comparable to that of emetine. Pharmacokinetics (Absorption): Rapid peak blood levels are achieved in 1 to 2 hours Distribution: It is widely distributed throughout the body and present in high concentrations in the liver, kidneys, lungs and crosses the placenta and appears in breast milk Protein binding: About 50% to 65% Excretion: Approximately 70% of a dose is excreted unchanged in the urine, and 10% in faeces. Acidification of the urine increases elimination of the drug. Small amounts of the drug may be present in the urine months following discontinuation of therapy.

Indications

Capquin is indicated for the prevention and treatment of malaria caused by P. vivax, P. ovale, P. malariae and susceptible strains of P.falciparum; Extra-intestinal amoebiasis (hepatic abscess) and rheumatoid arthritis.

Dosage and Administration

Prevention:

Adult: 500mg/week on the same day each week; beginning 1-2 weeks prior to exposure; continue for 4-6 weeks after leaving endemic area; if suppressive therapy is not begun prior to exposure, double the initial loading dose to 1000mg and give in 2 divided doses 6 hours apart, followed by the usual dosage regimen. Children: Administer 8mg/kg/week on the same day each week (do not exceed 300mg base/dose); begin 1-2 weeks prior to exposure; continue for 6 to 8 weeks after leaving endemic area; if the suppressive therapy is not begun prior to exposure, double the initial loading dose to 16mg base/kg and give in 2 divided doses 6 hours apart, followed by usual regimen.

Treatment:

Adult: 1000mg on day 1, followed by another 1000mg on day 2 and 500mg on day 3 Children: 16mg/kg on day 1, followed by another 16mg/kg on day 2, then 8mg/kg on day 3.

Over dosage and Treatment

Symptoms may occur in 30 minutes and consists of headache, drowsiness, visual changes, cardiovascular collapse and convulsions followed by sudden and early respiratory and cardiac arrest. Treatment is symptomatic, the stomach must be evacuated by emesis or gastric lavage. After lavage, activated charcoal may inhibit further absorption if given within 30 minutes of ingestion. Control convulsions before attempting gastric lavage. Acidification of the urine with ammonium chloride has been used to promote excretion.

Contraindications

Known or suspected chloroquine resistance in Plasmodium falciparum, porphyria, retinal damage, concurrent therapy with hepatotoxic drugs and previous hypersensitivity to chloroquine.

Warning and Precautions

Some strains of P. falciparium are resistant to 4-aminoquinoline compounds, so treatment with quinine or other specific treatment should be considered in such cases. Irreversible retinal damage has been observed in long term/high dosage treatment. So periodical ophthalmological examination should be contemplated. Muscular weakness may occur with chloroquine phosphate treatment. It may precipitate a severe attack of psoriasis. In patients with porphyria, condition may be exacerbated, in such patients the drug is to be withdrawn or avoided.

Interaction

Cimetidine may reduce the oral clearance rate and metabolism of chloroquine. Gastrointestinal absorption of chloroquine may be decreased by concomitant administration of kaolin or magnesium trisilicate.

Side Effects

Anorexia, nausea, vomiting, diarrhoea, abdominal cramps, hypotension, mild headache, psychic stimulation and ECG changes have been reported with chloroquine phosphate. Rarely nerve type deafness, tinnitis and reduced hearing may occur in few patients. Irreversible retinal damage, visual disturbance, scotomatous vision with field defects may also occur at times. Other side effects such as agranulocytosis, pruritis, neuropathy, blood dyscrasia, mucosal pigmentary changes and pleomorphic skin eruptions have been reported on prolonged therapy.

Presentation

Capquin is available as Capsules by 10’s and 500’s