Section III. ANTIMALARIAL AGENTS
4-14. INTRODUCTION
Malaria has been a critical problem for the American fighting man for decades.
Even with the pharmacological advances of today's modern medicine, strains of
resistant malaria are now rapidly spreading throughout endemic areas of the world. The
treatment of malaria requires extensive chemotherapy that is aimed at interrupting the
life cycle of the disease in man.
4-15. SPECIAL AGENTS
Several significant drugs have successfully treated forms of malaria. The agents
listed below work on either the blood or liver stages of malaria.
a. Chloroquine (Aralen). This drug acts only on the blood stages of the
parasite. It is the drug of choice for treatment of acute attacks in all types of malaria
except drug resistant strains of P. falciparum. Chloroquine is also very effective in the
prophylaxis of malaria. Side effects associated with the use of this agent are
gastrointestinal disturbances, anal pruritis, and visual disturbances. The visual
disturbances occur with prolonged use of the drug, which causes damage to the cornea
and retina.
b. Primaquine. Primaquine is an antimalarial agent used for the radical cure of
the relapsing forms of malaria caused by P. vivax or P. ovale. It is effective against
these types of malaria because it acts on the tissue stages of the parasite in the liver. It
is the presence of the parasite in the liver which, when not treated, may cause relapses
of the disease. The main side effect associated with this drug is hemolytic anemia.
This condition is frequently seen in patients lacking the G-6-PD enzyme, a genetic
defect that often occurs in dark skinned individuals and those of Mediterranean descent.
GI upset and visual disturbances have also occurred.
c. Chloroquine and Primaquine (CP). This agent is a combination drug
suitable for prophylaxis (prevention) of all types of malaria. Chloroquine and
Primaquine should not be given for acute attacks due to severe primaquine toxicity if
more than 26.3 mg of primaquine is given daily. Chloroquine and Primaquine tablets
are no longer the drug of choice for routine prophylaxis of malaria. The side effects of
CP are the same as those for the individual ingredients.
d. Pyrimethamine and Sulfadoxine (Fansidar). This combination is used in
the prophylaxis and treatment of malaria caused by organisms resistant to chloroquine.
Some of the side effects associated with this drug are hemolytic anemia and
gastrointestinal irritation. This drug should not be dispensed to pregnant or lactating
women.
MD0808
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