Nizonide tablets, containing the active ingredient nitazoxanide, are typically used to treat parasitic infections. The effects of nizonide 500mg generally start within a few hours of ingestion, and the medication continues to work in the body for about 24 to 48 hours. The full course of treatment usually spans 3 to 5 days, depending on the severity and type of infection. It is crucial to complete the entire prescribed course, even if symptoms improve early, to ensure the infection is fully eradicated. Consult a healthcare provider for specific guidance tailored to individual needs.