The incubation period is about two weeks (range 5 days to 20 days), but it can be much longer.
Many patients have no symptoms at all. Main complaints are intermittent diarrhea, steatorrhea, malabsorption, stomach pains, bloating, flatulence, and some nausea and vomiting.
Stool microscopy reveals cysts in most patients.
Metronidazole is effective in eradicating the disease. A repeat stool microscopy test 2 months after the initiation of therapy provides a good test for cure.