Question: how long does it take for metronidazole to kill trich?
Answer: It takes 7 days for the medicine to work. For 7 days after you take the pills: ∎ It is best not to have sex at all (vaginal sex, oral sex, anal sex, or using sex toys). ∎ If you do have sex, you must use a condom or else you will be in danger of getting trich again or passing the infection on to your partner(s).