Pyrimethamine
Pyrimethamine is an antiparasitic agent with broad-spectrum antiprotozoal activity. It is used to treat the parasitic diseases toxoplasmosis, cystoisosporiasis, and actinomycosis, and for the treatment and prevention of pneumonia.
It is on the World Health Organization’s List of Essential Medicines.
It is used in veterinary medicine to treat a tick-borne parasite that causes canine hepatozoonosis, and toxoplasmosis in small animals.