Allergy medication also helps against malaria
The active ingredient astemizole, which is otherwise administered for allergies, helps against malaria. The agent prevents the pathogens of the tropical disease from crystallizing heme molecules from the blood in their food vacuoles. Astemizole has a similar effect to the commonly used malaria drug quinoline.
Scientists at Johns Hopkins University led by David Sullivan came across astemizole while testing more than 2,600 drug candidates for their potential as a new antimalarial drug. Initial clinical tests had already confirmed that all substances were harmless for human use.
Astemizole actually reduces the parasite load of diseased rodents, as tests on mice have shown. In mice infected with pathogens that were not resistant to the old malaria drug chloroquine, the researchers even observed an eighty percent reduction in the number of parasites in the body. The drug was also effective against parasites resistant to chloroquine: Here the number of Plasmodium fell to less than half.
Astemizol is an antihistamine that doctors have so far only prescribed for allergies. The substance was withdrawn from the European market in the late 1990s because it rarely causes severe side effects. If astemizole is dosed too high in the body, it blocks potassium channels in the heart muscle and thus causes arrhythmias. Physicians nevertheless continue to prescribe the active substance in over thirty countries, including in the malaria-endemic regions of Cambodia, Thailand and Vietnam.
