Metronidazole

Metronidazole is an antimicrobial that kills bacteria and parasites. It’s used to treat a sexually transmitted disease (STD) called trichomoniasis.

Trichomoniasis is caused by the parasite trichomonas vaginalis and can be passed from person to person during sex. If you have trichomoniasis, you need to treat it with metronidazole because it will not go away on its own, and you can spread it to other people.

Whether you’re male or female, a trichomoniasis infection can make:

• your genitals feel itchy and sore
• you have discharge from your vagina or penis
• you have a burning sensation when you pee
• sex feel painful

You can also use metronidazole as an effective treatment for other infections like:

• rosacea on your skin
• tooth abscesses in your mouth
• bacterial infections in your vagina (bacterial vaginosis)
• ulcers or pressure sores
• Helicobacter pylori in your stomach
• colitis in your colon
• diarrhoea caused by giardiasis or clostridium in your gut
• pelvic inflammatory disease

To treat different types of infections, metronidazole comes in other forms such as a:

• cream
• gel
• liquid
• suppository
• intravenous injection (in hospital only)

Metronidazole works as an antiprotozoal to kill the trichomoniasis, which is a type of parasite called a protozoa. As an antibacterial, metronidazole also kills bacteria deep inside your body that do not need oxygen to stay alive.

When a parasite or bacteria causes an infection, metronidazole stops them from creating the DNA they need to multiply and spread. As a result, the microorganisms soon die out, and you start to feel better as the infection goes away.

You can take metronidazole to treat trichomoniasis if you are not allergic to nitroimidazoles or any other ingredients in metronidazole tablets.

Talk to you your doctor before taking metronidazole if you have:

• liver disease
• kidney disease or need regular kidney dialysis
• central nervous system problems
• peripheral neuropathy

Pregnancy and breastfeeding

If you’re pregnant or trying for a baby, you need to speak to a doctor for advice on whether metronidazole is safe for you to take.

If you’re breastfeeding, you need to speak to a doctor before taking metronidazole as it can pass into breast milk.

During your trichomoniasis treatment course, metronidazole can cause side effects such as:

• vomiting or feeling sick
• diarrhoea
• metal taste in your mouth
• feeling dizzy or sleepy

You should avoid driving and try to drink plenty of water to stay hydrated while taking metronidazole tablets. You should not drink alcohol while taking metronidazole tablets during your 7 day course and for 2 days after you complete it.

Signs of an allergic reaction to metronidazole tablets include:

• shortness of breath
• wheezing and difficulty breathing
• face and neck swelling

If you experience any of the above, you need to call 999 straight away as it is a medical emergency.

Metronidazole drug interactions

Metronidazole can interact with other drugs or medicines, and this can affect how the treatment works. Tell your doctor if you’re taking:

• blood thinners (anticoagulants), such as warfarin, aspirin or apixaban
• lithium
• epilepsy medications, such as phenytoin, primidone or phenobarbital
• 5 fluorouracil to treat cancer
• busulfan to treat leukaemia
• ciclosporin
• disulfiram

To find out more, take a look at the patient information leaflet in your pack of metronidazole.

If you get any side effects after taking metronidazole, you can report them using the MHRA Yellow Card Scheme online or on Google Play or the Apple App Store.

Which active ingredients does metronidazole contain?

The active ingredient in each metronidazole tablet is 400mg metronidazole.

Other ingredients in metronidazole tablets include povidone, magnesium stearate, colloidal anhydrous silica and maize starch.

Please check the patient information leaflet for any updates to the ingredients list of generic metronidazole tablets.

How should metronidazole be disposed of?

You can dispose of metronidazole by taking any unwanted or unused tablets to your local pharmacy. To help protect the environment, do not throw your metronidazole tablets in a sink, toilet or bin at home.

How should metronidazole be stored?

You should store metronidazole tablets in a cool area that is less than 25°C. Protect your metronidazole tablets from light by storing them in their original box.

What does metronidazole look like?

Metronidazole tablets look like white round tablets with MZ 400 written on one side.

In which pack sizes is metronidazole available?

Metronidazole comes in a blister strip of 7 or 14 tablets. A trichomoniasis treatment course is a pack of 14 metronidazole tablets.

Information on the manufacturer

The marketing authorisation holder of metronidazole is Milpharm Limited, Ares, Odyssey Business Park, West End Road, South Ruislip, HA4 6QD United Kingdom.

Metronidazole is manufactured by:

• Milpharm Limited (Ares, Odyssey Business Park, West End Road, South Ruislip, HA4 6QD United Kingdom)
• APL Swift Services (Malta) Ltd. (HF26, Hal Far Industrial Estate, Hal Far, Birzebbugia BBG 3000)