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34 Antiparasitic Drugs â–
Introduction to Antiparasitic Drugs
There is a tremendously unequal variation in the human burden of parasitic disease, based on geography, industrialization/hygiene, and immune status. It is estimated that up to half of the world’s population is chronically infected with parasites. The extent of parasite-related morbidity and mortality depends on parasite burden, preexisting immunity, and patient comorbidities. We will focus on parasitic diseases primarily affecting inhabitants of industrialized nations. Parasites causing human disease can be broadly grouped into two main categories, the unicellular protozoa and the multicellular helminthes ( Table 34–1 ). The protozoa have many subgroups, but we present them as primarily intestinal or primarily extraintestinal pathogens. The helminthes are subdivided into nematodes (roundworms), trematodes (flukes), and cestodes (tapeworms). Examples of common pathogens for each group are given along with some of the agents used in their treatment. Although not technically considered parasites, two other organisms that are susceptible to antiparasitic drugs will also be addressed: Pneumocystis jirovecii (technically a
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