Antiprotozoal agents (ATC code: ATC P01) is a class of pharmaceuticals used in treatment of protozoan infection.
Protozoans have little in common with each other (for example, Entamoeba histolytica, an unikont eukaryotic organism, is less closely related to Naegleria fowleri, a bikont eukaryotic organism, than it is to Homo sapiens, which belongs to the unikont phylogenetic group) and so agents effective against one pathogen may not be effective against another.
They can be grouped by mechanism or by organism. Recent papers have also proposed the use of viruses to treat infections caused by protozoa.
Antiprotozoals are used to treat protozoal infections, which include amebiasis, giardiasis, cryptosporidiosis, microsporidiosis, Malaria, babesiosis, trypanosomiasis, chaga's disease, leishmaniasis, and toxoplasmosis. Currently, many of the treatments for these infections are limited by their toxicity.
The mechanisms of antiprotozoal drugs differ significantly drug to drug. For example, it appears that eflornithine, a drug used to treat trypanosomiasis, inhibits ornithine decarboxylase, while the aminoglycoside antibiotic/antiprotozoals used to treat leishmaniasis are thought to inhibit protein synthesis.