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Antiprotozoal therapies

Peter F Weller, MD, MACP
Section Editor
Karin Leder, MBBS, FRACP, PhD, MPH, DTMH
Deputy Editor
Elinor L Baron, MD, DTMH


Protozoan parasites belong to four distinct groups: the amebae, the flagellates, the ciliates, and the sporozoa. Protozoa are single-celled organisms that replicate by various mechanisms within the infected host. The mechanisms of action of the various agents used to treat protozoan parasites are relatively poorly understood [1].

In the United States, the antiprotozoal drugs eflornithine, benznidazole, melarsoprol, nifurtimox, sodium stibogluconate, and suramin are available through the Centers for Disease Control and Prevention (CDC) Drug Service, Atlanta, GA 30333 (telephone 404-639-3670; drugservice@cdc.gov).

Agents with activity against protozoal parasites will be reviewed here; their use for treatment of specific protozoal infections is discussed in detail separately. Antimalarial agents are discussed in detail separately, as are agents with activity against helminths. (See "Antimalarial drugs: An overview" and "Anthelminthic therapies".)


Albendazole binds to tubulin and affects cytoskeletal microtubules and is a well-established therapy treatment of helminthic infections [2]. (See "Anthelminthic therapies".)

Albendazole also has activity against some protozoan infections, including most microsporidial species, particularly Encephalitozoon infections. However, it is not as active against Enterocytozoon bieneusi [3-10]. (See "Microsporidiosis".)

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Literature review current through: Nov 2017. | This topic last updated: May 26, 2017.
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