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Generic name: Metronidazole (oral or injection) [me-troe-NI-da-zole]
Names of brands: First Metronidazole, Flagyl
Classifications of drugs: amebicides, miscellaneous antibiotics

What is Flagyl?

Flagyl can be described as an antibiotic that helps treat infections caused by bacteria in the stomach, vagina, liver, skin joints, spinal cord, lungs, heart, or bloodstream. Flagyl can also be utilised for treating trichomoniasis, which is a sexually transmitted illness caused by a parasite. In most cases, both partners are treated simultaneously, even if one of them has no symptoms. Do not take Flagyl for any condition that hasn't been evaluated by your physician.


It is not recommended to take Flagyl if you've recently drunk alcohol or consumed disulfiram (Antabuse) in the last 2 weeks. Don't consume alcohol or eat food or medicines containing propylene glycol while on Flagyl or for a minimum of three days after the last day of taking it.

The presence of seizures and other nerve system disorders has been observed in patients receiving Flagyl. It is recommended to stop taking the medication immediately if you suffer from any neurological symptoms like headaches, seizures, and visual disturbances, as well as weakening, numbness, or sensations of tingling. This medication is not able to cure a viral infection, like the common flu or cold. In studies on animals (mice or rats), this medication caused certain kinds of cancers or tumours. It isn't known if these side effects will occur for people who take this medication. Consult your physician about the risk.

Before taking this medicine

It is not recommended to use Flagyl in the event that you are allergic to metronidazole (secondazole), secnidazole, or tinidazole, or if:

  • You consumed alcohol within the last 3 days;
  • You consumed food or other substances that contain propylene glycol within the last 3 days. You took medication or food that contains propylene glycol in the last 3 days.
  • You took disulfiram (Antabuse) in the past 14 days.

Could harm a baby who is not yet born. Don't use metronidazole to treat trichomoniasis in the very first three months of your pregnancy. Inform your doctor when you are pregnant. The majority of uses for metronidazole have been approved for the treatment of teens and children. Metronidazole is not approved for the treatment of vaginal infections among girls who haven't started menstrual cycles.

To ensure that you are able to safely use Flagyl, inform your doctor if you've previously had:

  • Liver disease;
  • Renal disease (or if you're taking dialysis);
  • A heart rhythm disorder
  • An intestinal or stomach disease like Crohn's disease;
  • An illness of the blood cells like anaemia (lack of red blood cells) or low white blood cell (WBC) counts;
  • An infection caused by fungal organisms anywhere on your body.
  • A nerve disorder.

In studies on animals, metronidazole was found to cause certain kinds of tumors, including  a few that were considered to be cancerous. However, it's not yet known if these effects could be observed in humans. Consult your physician about the risk. It is not recommended to feed your baby within 24 hours of taking Flagyl. If you utilise a breast pump during this period, take the milk away and don't give it to your child.

How to take Flagyl?

You should take Flagyl exactly as directed by your physician. Follow the instructions on the label of your prescription and also read the medication guide or instructions sheets. Flagyl oral is taken through the mouth. Flagyl injection is administered as an infusion to veins. Your healthcare provider will offer you this injection if you are not able to get the medicine through your mouth.

Then shake up your oral suspension (liquid). Use the measuring device supplied (not a spoon from the kitchen). Take these tablets with extended release, and don't crush, chew, or break them. If you're dealing with a vaginal infection, your partner could require Flagyl to ensure that you don't get infected again. The usual dosage is at least 10 days consecutively. It's possible that you'll need to repeat this dose several weeks later.

Use this medication even if symptoms get better. Inadequate doses can cause your illness to become intolerant to medications. Flagyl does not treat a viral disease (flu or a general cold). Flagyl does not treat a vaginal yeast infection. It is possible to have an infection in your vagina that needs treatment with an antifungal medicine. Consult your physician if you are experiencing symptoms like an itch or discharge following treatments with Flagyl. Do not share this medication with anyone else, even if they suffer from similar symptoms to yours.

This medicine may affect the results of certain tests. Inform any physician who treats you that you're taking this medication. Place it in a cool, dry place far from heat and moisture.

What happens If I miss the dose?

You should take the medication as quickly as you can. However, avoid any missed doses if it's close to the time of the next dose. Don't take two doses at once.

What happens If I overdose?

Get medical attention in an emergency or contact the Poison Help line toll-free at 1-800-222-1222. Overdose symptoms can include vomiting, numbness, burning sensations, or issues with balance or movement.

What should be avoided?

When you are taking Flagyl and for the three days following the final dose Avoid drinking alcohol or eating foods such as medicines or products that contain propylene glycol. There are some unpleasant side effects, such as headaches, nausea, stomach cramps, vomiting, and tingling or warmth beneath your skin.

Side effects of Flagyl

Seek medical attention immediately. If you are experiencing symptoms warning of an allergic reaction to Flagyl (hives or itching, sensation of warmth or tingling, joint pain, fever, dry, dry vagina, stuffy nose, difficulty breathing, swelling of your throat or face) or an extremely severe skin reaction (fever or sore throat, burnt eyes, ache, and red or purple skin itching and peeling),

Contact your doctor immediately if you are suffering from:

  • New or worsening symptoms of infection that are not as severe or new;
  • Urination that is painful or difficult
  • Confusion;
  • Feeling lightheaded (like it's possible to get drunk);
  • vaginal discharge or itching vaginal discharge or itching
  • The appearance of blisters or ulcers on your mouth, swollen or red gums, or difficulty swallowing.

Stop taking the medication and consult your physician now if you are suffering from neurological adverse effects (more likely to happen while taking metronidazole over a long period):

  • Tingling, numbness, and burning sensations in your feet or hands;
  • Vision issues eye pain when experiencing flashes of light
  • Muscle weakness, difficulties with speech, or coordination
  • Difficulty speaking or understanding what's being said to you.
  • A seizure;
  • Neck stiffness, fever, and heightened sensitivity to light.

Metronidazole may cause serious liver issues in patients with Cockayne syndrome. If you have this disorder, take a break from Flagyl and consult your physician in the event that you exhibit indications of liver disease, such as nausea, stomach discomfort (upper right corner), and dark urine. stool that is coloured with clay and jaundice (yellowing of the eyes or skin).

Some side effects are more common in older people.

Common flagyl adverse effects could include:

  • Depression,
  • Sleeplessness,
  • Headache,
  • Dizziness,
  • Weakness;
  • Nausea, vomiting, loss of appetite, stomach pains;
  • Diarrhoea,
  • Constipation;
  • Unpleasant metallic taste
  • Rash,
  • Itching;
  • Vaginal itching or discharge; pain during sex;
  • Mouth sores, or
  • Swelling, redness, as well as a "hairy" tongue.

This isn't a complete list of all the side effects. Other side effects could occur. Consult your physician for advice regarding medical effects. You can report any side effects to the FDA at 1-800-FDA-1088.

Interaction with other drugs

It is sometimes not safe to use certain medications in conjunction with other medications. Certain medications can alter your blood levels from other medications that you are taking, which can create side effects or render the medication less effective.

Discuss with your doctor your current medications. There are many drugs that can affect metronidazole, particularly:

  • An antidepressant
  • Asthma medication;
  • Busulfan and other cancer drugs;
  • Heart or blood pressure medications
  • lithium or other antipsychotic medicines;
  • Medicines to treat the symptoms of malaria, HIV, or other infections medicine to treat malaria, HIV, or other infections
  • Is a blood thinner: warfarin, coumadin, and Jantoven.

This list isn't complete, and a variety of other medications could react with metronidazole. This includes over-the-counter and prescription medications, vitamins, and herbal supplements.



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