Metronidazole Side Effects

Metronidazole is a prescription antibiotic that can provide effective treatment for a varied range of infections, including bacterial vaginosis, rosacea, gum infections and dental abscesses. It comes available as tablets, a topical gel, suppositories or a liquid, making it easy and convenient to treat the condition in question.

However, like all medicines, taking metronidazole can cause side effects in some people.

Before you buy Metronidazole 400mg tablets, we recommend familiarising yourself with the different side effects that can potentially appear during your treatment.

This guide will be looking into both the common and more serious side effects of taking metronidazole, as well as providing you with guidance on what to do if you experience any of them.

Common side effects

The most common side effects of metronidazole are:

• Nausea
• Vomiting
• Diarrhoea
• A furry tongue
• Metallic taste in the mouth
• Constipation
• Dizziness

If any of these side effects start to concern you or do not go away on their own, consult your doctor. Do not stop taking the medication unless they tell you to. Stopping your treatment before your doctor tells you may mean that the infection does not clear, or it may come back.

If you have a very furry tongue, you may be suffering from thrush, which can happen as a result of taking antibiotics. Talk to your doctor or pharmacist if this occurs.

Some people may find that metronidazole turns their urine a darker colour. This is not a cause for concern and should revert once you stop taking it.

Serious side effects

It is unlikely you will get any serious side effects while taking metronidazole, as these affect less than 1 in 1,000 people who use it.

Nonetheless, you should contact your doctor or call 111 immediately if you experience any of the following:

• Blurred or double vision
• The skin or whites of your eyes start to turn yellow
• You have severe stomach pains that may travel to your back
• You have a stiff neck accompanied by a high temperature, you are hallucinating, feel confused, are finding it hard to speak or are sensitive to light

These may be symptoms of a more serious problem. The symptoms listed in the final bullet point may be signs of meningitis, or that the medicine is affecting the brain.

Serious allergic reaction to metronidazole

If any of the following symptoms occur while you are using metronidazole, you should either go to A&E or call 999 straight away. These could be signs that you are having an allergic reaction that needs to be treated in hospital:

• You have a skin rash that may be red, peeling, itchy, swollen or blistering
• You have any breathing problems or are finding it hard to speak
• You are wheezing
• Your mouth, face, tongue, lips or throat start to swell
• Your throat or chest feels tight

How to cope with the side effects of metronidazole

The common side effects of metronidazole will normally go away on their own after a few days. In the meantime, there are certain tactics you can use to reduce their impact on your daily life.

If you experience vomiting or diarrhoea, you should make sure that you drink plenty of water to avoid becoming dehydrated. If you are vomiting, you can stay hydrated by taking small sips of water at regular intervals. Speak to your doctor or call 111 if you have still got diarrhoea or vomiting after one day.

To remedy a furry tongue or metallic taste in the mouth, you should also drink a lot of water. Eat plain foods until the problem has gone away.

Nausea can normally be eased by eating plain meals that do not have strong flavours or smells. To lessen the risk of feeling sick, you should take metronidazole after food.

How long do metronidazole side effects last?

Metronidazole’s most common side effects should resolve themselves quite quickly. If you do get any of the common side effects, most will clear up within a few days.

You should seek medical attention if you experience vomiting and it does not stop after 24 hours.

If you get any of the serious side effects, or exhibit symptoms of an allergic reaction, you should seek medical attention immediately and not wait for the symptoms to go away on their own. These side effects will need to be treated by a doctor.

Does metronidazole make you tired?

Drowsiness is not a common side effect when taking metronidazole, with that said; drowsiness is listed in the very rare side effects affecting less than 1 in 10,000 users.

Whilst it is unlikely that you will suffer drowsiness when taking metronidazole, we recommend contacting your doctor if you experience any signs or symptoms of drowsiness.

Will metronidazole give me thrush?

Antibiotics can commonly cause a fungal infection called thrush. Antibiotics kill the harmless and helpful bacteria that helps to protect you from getting thrush. Thrush is typically more common when using the gel or cream version of this product.

Can I drink alcohol with Metronidazole?

You must not drink alcohol with metronidazole as it is classed as a disulfiram-like drug which means that it can cause an adverse reaction to alcohol.

You should also refrain from drinking for 72 hours after finishing your treatment.

You can read more information on metronidazole and alcohol in our helpful medical guide.

Summary

While it is not likely that you will get side effects during the use of metronidazole, there is still a possibility. The milder side effects will usually go away on their own in a day or so, but they should still be assessed by a doctor if they persist or become serious.

Despite the likelihood of getting serious side effects being very low, anyone who does experience any serious adverse problems should contact their doctor or dial 111 immediately.

As with any medicine, you should always make sure you read the patient information leaflet for a full list of side effects. This leaflet will come with your medication when you buy it and will provide a comprehensive list of known side effects, as well as advice on what to do if they affect you.

Sources

https://www.nhs.uk/medicines/metronidazole/

https://www.webmd.com/drugs/2/drug-6426/metronidazole-oral/details

https://bnf.nice.org.uk/drug/metronidazole.html#sideEffects