Contraindications for Metronidazole

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Flagyl from $0.51 per pill

Before you take Flagyl (Metronidazole)

Do not take Flagyl and tell your doctor if:

  • You are allergic (hypersensitive) to metronidazole, nitroimidazoles (eg tinidazole) or any of the other ingredients of your medicine.
  • Signs of an allergic reaction include: rash, swallowing or breathing problems, swelling of the lips, face, throat, or tongue.

Do not take Flagyl if any of the above applies to you. If you are not sure, talk to your doctor or pharmacist before taking Flagyl.

Take special care with Flagyl and consult your doctor or pharmacist before using your medicine if:

  • You have or have had a liver problem
  • You are having kidney dialysis
  • You have a nervous system disease

If you are not sure if any of these apply to you, talk to your doctor or pharmacist before taking your medicine.

Taking other medicines with Flagyl (Metronidazole)

Tell your doctor or pharmacist if you are taking or have recently taken any other medicines. This includes over-the-counter medicines, including herbal medicines. This is because Flagyl may affect the way some other medicines work. In addition, some other medicines may affect the way Flagyl works.

Pregnancy and lactation

Tell your doctor before using Flagyl if:

  • You are pregnant, you may become pregnant, or you think you may be pregnant. Flagyl should not be taken during pregnancy unless absolutely necessary.
  • You are breastfeeding. It is best not to use Flagyl if you are breastfeeding. This is because small amounts can pass into breast milk.

How to take Flagyl

Always take Flagyl exactly as your doctor has told you. It is important to complete a complete course of treatment. The duration of a course will depend on your needs and the disease being treated.

Take Flagyl with food and drink.

Do not drink alcohol while you are taking Flagyl and for 48 hours after you finish your course. Drinking alcohol while using Flagyl can cause unpleasant side effects such as feeling sick (nausea), being sick (vomiting), stomach pain, hot flashes, very fast or irregular heartbeats (palpitations), and headache.

Check with your doctor or pharmacist if you are not sure.

  • Swallow the tablets whole with a drink of water.
  • Do not crush or chew the tablets
  • Take these tablets during or right after a meal

To treat bacterial infection


  • The starting dose is 800 mg
  • After 8 hours, take another 400mg dose and repeat this dose every 8 hours


  • Your doctor will determine how much your child should take depending on their weight
  • Repeat dose every 8 hours
  • If your child is a baby less than 8 weeks old, your doctor will give you a daily dose or two separate doses of 12 hours

To prevent infections after surgery


  • Start taking Flagyl tablets 24 hours before your surgery
  • Take 400 mg Flagyl every 8 hours
  • After the operation you can give Flagyl either by dripping into a vein or rectally as a suppository until you are able to take tablets again


  • Give your child Flagyl tablets 1-2 hours before your surgery
  • Your doctor will determine how much your child should take depending on their weight
  • After the operation, your child may be given Flagyl either by dripping into a vein or rectally as a suppository until they can return to taking tablets



I have a very negative attitude of taking drugs at all, but if you have already prescribed medications, then I try to choose those without a negative effect on the stomach. I treated trichomoniasis with Flagil. It’s a very unpleasant disease with severe pain during urination. Everything went fine and I did not notice any negative side effects. The most important thing is to exclude alcohol when taking this medication and then everything will go nice and quiet, so the bacteria will be quickly destroyed.


Have found Gardnerelosis during annual preventive survey. At first I was terribly frightened, but it turned out that it was something like a Dysbiosis. For treatment, the doctor prescribed this drug. Flagyl works fine, but in my case causes burning and nausea. Unpleasant, of course, but you can live with it. The main thing is that the illness has passed. My BFF also prescribed Flagyl for the treatment of ureaplasma. But she had no such side effects. Probably, it is all individual reaction of my body to this medicine. All the same you should consider possibility of occurrence of the given side effects.