Why isnt the trich infection going away? Does it take a month to cure or do I need to go back for a second or diffrent dose?

Reinfection. Trichomonas is very easy to treat and treatment failures are uncommon. A single dose of Flagyl (metronidazole) is almost always effective for treating trichomonas, and should take less than three days to work. If you have persistent infection, you may need a longer treatment period with antibiotics. You should be sure your partner is treated so that you are not being reinfected.