Metronidazole

Metronidazole is an antibiotic that clears up infections by stopping the bacteria from growing. It’s available in various forms, including tablets, gel, and cream. Metronidazole is a prescription medicine and is not available to buy over the counter.

It’s used to treat a range of bacterial and parasitic infections, including bacterial vaginosis (BV) and trichomoniasis. It can also be used to treat skin and mouth infections, rosacea, and infected ulcers or wounds.

When it’s used to treat BV, metronidazole targets the bacteria causing the infection and helps restore the natural balance of vaginal bacteria. By reducing the number of harmful bacteria, metronidazole can eliminate the infection and relieve any symptoms you may be experiencing.

Unlike BV, trichomoniasis is caused by a parasite (trichomonas vaginalis), not by bacteria. Metronidazole clears up the infection by killing the parasite that causes trichomoniasis.

We offer metronidazole in tablet or gel form. Swallow tablets whole with a glass of water with some food, twice a day. If you’re using metronidazole gel, it should be inserted directly into the vagina using the applicator provided.

If you’re taking metronidazole as a tablet, it’s important that you make sure:

• Take it with, or after food and DO NOT CHEW.
• Swallow tablets with plenty of water, and take them with a meal or snack.
• Do not drink alcohol with the metronidazole and for 48h after finishing the course.

You must continue to use the treatment as prescribed until the full antibiotic course is finished. Do not stop using metronidazole if your symptoms become better before then. This ensures the complete elimination of the infection and reduces the risk of it coming back.

The usual dose for treating both BV and trichomoniasis with metronidazole tablets is 400mg taken twice a day for seven days.

If you’re taking metronidazole gel to treat BV, fill one of the disposable applicators that come with the gel with 5g of gel and gently insert it into your vagina. Push the plunger to release the gel and then dispose of the applicator. Use the metronidazole gel once a day at bedtime, for a total of five days.

We can prescribe metronidazole 400mg tablets for the treatment of BV or trichomoniasis, or a vaginal gel containing metronidazole for the treatment of BV if suitable for you. Find out more about the BV treatments and trichomoniasis treatment we offer.

Yes, metronidazole is an effective treatment for BV and trichomoniasis when used correctly and the full course is finished. In most cases, both BV and trichomoniasis symptoms should improve within a few days of starting treatment. However, if your symptoms haven’t improved or persist beyond two weeks, you should see your GP or healthcare provider to rule out other possible causes.

Like with any medicine, you may experience some side effects while taking metronidazole. Common side effects include: nausea and vomiting; a change in the way things taste, furred tongue, or sore mouth; lack of appetite. You may also find your urine is darker while you’re taking it. This isn’t harmful and will pass. Just make sure to drink plenty of clear fluids.

Please read the Patient Information Leaflet for full details on possible side effects.

If you’re concerned about any side effects, please talk to your pharmacist or regular healthcare provider.

Metronidazole is classified as a strong antibiotic due to its broad-spectrum activity against various anaerobic bacteria, including those associated with BV and trichomoniasis. You should avoid drinking any alcohol while taking metronidazole and for at least 48 hours after completing the course of treatment. These could interact with metronidazole and make you feel very unwell.

Metronidazole should not be taken if you’re pregnant or breastfeeding, think you might be pregnant or are trying to have a baby. Ask your doctor or pharmacist for advice before taking this medicine.

You should tell your doctor or pharmacist if you’re allergic to metronidazole, as they might be able to prescribe alternative treatment.

If you don’t want to use metronidazole for BV or it’s not right for you, there are alternative treatments that can help. Clindamycin is another antibiotic that works in a similar way to treat BV.

You can ask your regular GP for a prescription or complete our quick online questionnaire for convenient, fast BV treatment. One of our qualified clinicians will review everything and prescribe BV treatment for you if suitable. It can then be collected from your local Boots pharmacy or sent directly to your door in discreet packaging if you prefer.

Visit the Boots Online Doctor BV Treatment service.

Metronidazole is very effective at treating trichomoniasis. However, if you have an allergy to metronidazole or are unable to take it for a trichomoniasis infection, you will need to see your GP or visit a sexual health centre to discuss what alternative treatments are available.

Preventing BV can be challenging, as it’s not always obvious why it starts and it can come back even after it clears. Hormonal changes during your menstrual cycle, menopause or pregnancy can change the natural balance of bacteria in your vagina. Having unprotected sex and smoking can also contribute to an imbalance of bacteria and lead to BV.

There are some things you can do to help reduce the risk of getting BV again by maintaining the natural balance of bacteria in your vagina. This includes avoiding perfumed bath oils and hygiene products, douching, or wearing thongs and tight nylon tights.

Find out more about BV and how to prevent it.

Unfortunately, there are no non-drug alternatives to treating trichomoniasis. You also can’t develop an immunity to trichomoniasis if you’ve had it before and can catch it again.

Trichomoniasis is a sexually transmitted infection. The best way to prevent trichomoniasis is to have safe sex by using a condom. If you've been diagnosed with trichomoniasis, it’s important that both you and your partner, as well as any other recent partners, are tested and treated for trichomoniasis as well as other STIs to prevent the infection from spreading. You should also avoid any sexual contact until you and your partner(s) have completed treatment and for at least 7 days after this, to prevent re-infection.

Find out more about trichomoniasis and how to prevent it.

BV, or bacterial vaginosis, is a vaginal infection that is quite common in women of child bearing age. Any woman can get BV, including women in same sex relationships and women who have never had sex. Although BV isn’t a sexually transmitted disease (STI), it can be triggered by having unprotected sex and it can increase your risk of catching a STI. It can also cause complications in pregnancy if left untreated.

BV is caused by an imbalance in the natural bacteria present in the vagina. The vagina contains a delicate balance of different bacteria, but when that balance is disrupted and harmful bacteria overgrow, it can result in BV. It isn’t dangerous and many women have it without experiencing symptoms. You only need treatment if you’re experiencing symptoms, such as a fishy smell or watery grey or white vaginal discharge.

Find out more about BV treatment options.

Trichomoniasis is a common sexually transmitted infection (STI) caused by a parasite (trichomonas vaginalis). The parasite can be found in both men and women and is typically transmitted during unprotected vaginal sex and sharing sex toys. Most people infected with trichomoniasis will have no symptoms which can make it difficult to diagnose and easy to spread. Symptoms include:

• pain and discharge from the vagina or penis
• urination and sex may become painful
• In women, the vulva and vagina may be itchy and uncomfortable

Although trichomoniasis is treatable and typically doesn’t have any serious long-term effects, it can make you more vulnerable to catching other STIs.

Note: If you develop a temperature, lower tummy pain, or (if male) painful or swollen testicles, please seek urgent medical attention.

It's important to note that BV is not an STI itself. Its symptoms typically include a thin grey or white vaginal discharge and a fishy smell. However, if you experience soreness and itching along with these symptoms, it may indicate an STI or another infection. If you have concerns about these symptoms, you should get tested at your GP or local sexual health clinic to determine the underlying cause.

Metronidazole belongs to a class of antibiotics called nitroimidazoles, and when combined with alcohol, it can cause a severe reaction known as the disulfiram-like reaction. This will cause you to feel very unwell with unpleasant symptoms such as flushing, headache, and rapid heartbeat.

How fast metronidazole tablets work can vary from person to person. In most cases, symptoms improve within a few days of starting treatment. If your symptoms don’t go away within two weeks of starting treatment, or start to come back, please see your GP or local sexual health clinic for further help.

There is a common misconception that eating bananas should be avoided while taking metronidazole. However, there’s no scientific evidence to support this claim. Bananas do not interact with metronidazole or interfere with its effectiveness. It’s important to follow a balanced diet and maintain good hydration while taking metronidazole to support overall health and wellbeing.

In some cases, BV may recur even after treatment with metronidazole. This can happen when the course of treatment isn’t completed or due to other underlying factors that contribute to the imbalance in vaginal bacteria. If BV symptoms persist or recur after completing a course of metronidazole, please let us know via your online patient record or talk to your regular healthcare provider to discuss next steps.

Some things you can do to avoid getting BV are:

• Always finish the entire course of treatment for BV, even if the symptoms go away after a few doses
• Use condoms when having sex
• Smoking can change the balance of bacteria in your vagina so stopping smoking can help prevent BV from coming back
• Avoid douching. The vagina can maintain a healthy balance of bacteria on its own - douching can upset this balance and potentially flush harmful bacteria into the uterus and fallopian tubes
• Avoid using perfumed oils and lotions around and inside the vagina

Some things that you can do to avoid getting trichomoniasis are:

• Always finish the entire course of treatment for trichomoniasis, even if the symptoms go away after a few doses
• Use condoms when having sex
• Make sure that both you and your partner, as well as any other recent partners, are treated for trichomoniasis even if only one of you has been diagnosed. It’s possible to have a trichomoniasis infection and not have any symptoms so it’s important that both of you are treated in order to stop the infection from spreading or coming back
• If you know that you have trichomoniasis and are receiving treatment, it’s important that you stop having sex (oral, anal and vaginal) for at least a week after you and your sexual partner have been treated