Antimalarial Drugs Health Article

Definition

Antimalarial drugs are medicines that prevent or treat malaria.

Purpose

Antimalarial drugs treat or prevent malaria, a disease that occurs in tropical, subtropical, and some temperate regions of the world. The disease is caused by a parasite, Plasmodium, which belongs to a group of one-celled organisms known as protozoa. The only way to get malaria is to be bitten by a certain type of mosquito that has bitten someone who has the disease. Thanks to mosquito control programs, malaria has been eliminated in the United States, almost all of Europe, and large parts of Central and South America. However, mosquito control has not worked well in other parts of the world, and malaria continues to be a major health problem in parts of Africa, Southeast Asia, Latin America, Haiti, the Dominican Republic, and some Pacific Islands. Every year, some 30,000 Americans and Europeans who travel to these areas get malaria. People planning to travel to the tropics are often advised to take antimalarial drugs before, during, and after their trips, to help them avoid getting the disease and bringing it home with them. These drugs kill Plasmodium or prevent its growth.

In recent years, some strains of Plasmodium have become resistant to antimalarial drugs, and medical researchers have stepped up efforts to develop a malaria vaccine. In early 1997, researchers reported encouraging results from a small study of one vaccine and planned to test the vaccine in Africa.

Description

Antimalarial drugs are available only with a physician's prescription. They come in tablet, capsule, and injectable forms. Among the commonly used antimalarial drugs are chloroquine (Aralen), mefloquine (Lariam), primaquine, pyrimethamine (Daraprim), and quinine.

Recommended dosage

Recommended dosage depends on the type of anti-malarial drug, its strength, and the form in which it is being used (such as tablet or injection). The dosage may also be different for different people. Check with the physician who prescribed the drug or the pharmacist who filled the prescription for the correct dosage. Always take this medicine exactly as directed, and keep taking it for the full time of treatment. If the drug is being taken to treat malaria, do not stop taking it just because symptoms begin to improve. Symptoms may return if the drug is stopped too soon. Never take larger or more frequent doses than the physician has ordered, and do not take the drug for longer than directed.

Travelers taking this medicine to prevent malaria may be told to take it for one to two weeks before their trip and for 4 weeks afterward, as well as for the whole time they are away. It is important to follow these directions.

Antimalarial drugs work best when they are taken on a regular schedule. When taken once a week to prevent malaria, they should be taken on the same day every week. When taken daily or several times a day to treat malaria, they should be taken at the same time every day. Doses should not be missed or skipped.

Some antimalarial drugs should be taken with meals or with milk to prevent upset stomach. Others must be taken with a full glass of water. Be sure to follow directions for the best way to take the drug that is prescribed.