Brick said: "Tinidazole works way better for Giardia than Flagyl, with fewer side effects" http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0000280/ I will second that statement. Tinidazole works fast and you take it all in one dose. My doctor writes me a scrip before I go so I have the pills with me. When you need them, you need them RIGHT NOW! Palomino