Metronidazole

About Metronidazole 400 mg Tablets

Metronidazole 400 mg tablets are a first-line prescription-only antibiotic used to treat bacterial vaginosis (BV). BV occurs when the natural balance of bacteria in the vagina is disrupted, often leading to discharge and an unpleasant odour. It’s very common and easily treated with a short course of antibiotics. Metronidazole works quickly to restore the natural balance and provide reliable relief when you need it most.

Metronidazole is a versatile medication because it targets anaerobic bacteria (bacteria that thrive in environments with low oxygen levels) and protozoal infections. This means it’s not only used for BV, but also for other conditions. Because it’s taken by mouth, the medicine works throughout the body, reaching the infection site through the bloodstream.

You can buy Metronidazole 400 mg pills online from reputable companies such as Prescription Doctor. Simply complete a short medical questionnaire, and our clinicians will review your answers to determine whether the treatment is suitable for your circumstances. 
 

Metronidazole Prices

Prescription Doctor is pleased to offer Metronidazole tablets at the following prices:

We also offer alternative treatments for bacterial vaginosis, such as Dalacin Cream and Zidoval. 

What is Metronidazole Used For?

Metronidazole is primarily prescribed for bacterial vaginosis, but that’s only part of the picture. It’s also used to treat other infections caused by anaerobic bacteria, such as dental, bone and joint, and certain abdominal infections. Doctors may also recommend it for protozoal infections, such as trichomoniasis, amebiasis, rosacea, and giardiasis.

In some cases, metronidazole is combined with other medicines to treat Helicobacter pylori, the bacteria that can cause stomach ulcers. Its wide range of uses makes it one of the most frequently prescribed antibiotics worldwide. For BV specifically, metronidazole remains a first-choice treatment. It’s effective, straightforward to take and has been safely used for decades.

Metronidazole is available in various forms, including tablets, gels, and suppositories. Prescription Doctor can approve both the tablets and gel for the treatment of bacterial vaginosis. 

How Do Metronidazole Tablets Work?

Metronidazole works by interfering with the DNA of bacteria and protozoa. Once inside the microorganism, it’s converted into an active form that binds to the DNA and stops it from replicating. Without the ability to reproduce, the bacteria or protozoa die, clearing the infection.

This mechanism is particularly effective against anaerobic bacteria, which are commonly responsible for BV and other low-oxygen infections. By targeting them directly, metronidazole helps restore balance to the vagina or treat infections elsewhere in the body.

Because metronidazole is taken orally, the medication is distributed throughout the bloodstream and can treat infections at multiple body sites. This makes it a versatile treatment option that goes beyond just BV.
 

How Effective Are Metronidazole Antibiotics? 

Metronidazole is considered one of the most reliable treatments for BV. Clinical studies show cure rates of 70–90% after a single 7-day course, making it a gold-standard option. Meanwhile, a study comparing Metronidazole to Clindamycin showed that over 90% of participants had no BV symptoms after treatment, regardless of which medication they used.

Like with other BV treatments, recurrence is common. A high proportion of women can experience it again within 6 months. In those cases, your doctor may recommend another course of metronidazole, an alternative antibiotic or longer-term strategies to help maintain vaginal health.

Outside of BV, metronidazole is highly effective for protozoal infections like trichomoniasis and giardiasis, with cure rates above 80%. Its broad effectiveness explains why it’s been trusted by clinicians for several decades.

How Long Does Metronidazole Take to Work? 

Most women notice improvements in discharge and odour within 2–3 days, though the full course must be completed to get the best results. If your symptoms have not improved or persist for more than two weeks, it’s essential to consult your GP, as there may be other possible causes of the infection. 

Metronidazole Prescription Criteria

Metronidazole is a prescription-only medicine (POM), so you’ll need to be assessed by a healthcare professional before it can be supplied.

You may be prescribed metronidazole if:

• You’ve been diagnosed with BV or another infection sensitive to metronidazole
• You don’t have an allergy to metronidazole
• You’re able to avoid alcohol during treatment and for 48 hours afterwards
• You don’t have a history of severe liver problems or neurological conditions

Metronidazole may not be suitable if:

• You’re pregnant in the first trimester (unless your clinician decides it’s essential)
• You’re breastfeeding and haven’t been advised that it’s safe
• You’re taking medicines such as warfarin (risk of increased bleeding) or certain epilepsy treatments
• You’ve previously had serious side effects, such as seizures or nerve damage, while on the drug

Your clinician will review your full medical history before prescribing metronidazole to ensure it is both safe and effective for you.

Metronidazole 400 mg: How to Take

Metronidazole tablets should be swallowed whole with a glass of water. Taking them with or after food can reduce the chance of stomach upset. For BV, the typical treatment course is 5-7 days. Try to take your doses at evenly spaced times (usually morning and evening) to keep a steady level of medicine in your system. Even if your symptoms clear up quickly, always complete the course to reduce the risk of BV returning.

You should always take Metronidazole 400 mg tablets exactly as instructed by your prescriber. 

Metronidazole Dosage Information

For bacterial vaginosis, the standard regimen is 500 mg twice a day for 7 days. Depending on your individual case, your doctor may prescribe a different dose, ranging from 250 mg to 1,000 mg. Sometimes, a single larger dose (2g) may be prescribed, although this is less common due to a higher risk of side effects.

If you’re following the standard Metronidazole dosage schedule, you should aim to take the two doses at least 8 hours apart. For other conditions, such as trichomoniasis or giardiasis, dosing schedules may vary.

Important: Do not drink alcohol during treatment or for at least 48 hours after your last dose. Combining alcohol with metronidazole can cause severe nausea, flushing and headaches.

What Happens if I Miss a Dose of Metronidazole?

If you forget to take Metronidazole 400mg, take it as soon as you remember. If it is near the time of your next dose, skip the missed dose and continue taking Metronidazole as usual. Do not take a double dose to make up for any missed doses.

If you have any questions about dosing or any other aspects of treatment, contact your healthcare provider.

Metronidazole Side Effects  

Much like all medications, Metronidazole can cause side effects. These are normally mild and don’t last long. Some people may experience no adverse effects when taking the treatment.

Potential Metronidazole side effects include:
 

The above is not an exhaustive list of Metronidazole side effects. For more information, refer to the Patient Information Leaflet included with the medication.  

You should stop taking Metronidazole and consult your doctor immediately if you experience any of the following:

• Bleeding gums
• Bruising
• Fatigue
• Stomach pain which radiates to your back (pancreatitis)
• Ulcers in the mouth
• Unexpected infections
• Yellowing of the skin and eyes (jaundice)

How Long Do Metronidazole Side Effects Last?

Metronidazole side effects can last from several hours to a few days, though the latter usually occur when treatment is stopped. Most people will start to notice side effects after around 30 minutes of taking the medication, while some users will experience them each time they take a dose.

If your side effects persist or worsen, consult your doctor or healthcare provider. They may be able to recommend an alternative treatment that’s better suited to your circumstances. 

How to Handle Metronidazole Side Effects

Most Metronidazole side effects can be managed at home. Taking the tablets with food can help reduce the risk of problems occurring. Using over-the-counter medications like ibuprofen or paracetamol can help soothe headaches. Constipation can be treated by increasing your fibre intake. For nausea, vomiting, and diarrhoea, you should stay hydrated and get plenty of rest. 

Metronidazole Allergic Reactions

Do not take Metronidazole if you are allergic to Metronidazole or any of its other ingredients listed in the patient information leaflet. If you notice signs or symptoms of an allergic reaction, stop taking Metronidazole and consult your doctor, or go directly to your nearest hospital. Remember to take the packaging and any remaining medication with you, so doctors know exactly what you have taken.

Signs of an allergic reaction to Metronidazole include:

• Blue skin or lips
• Collapse or loss of consciousness
• Difficulty breathing
• Dizziness and confusion
• Rash
• Severe stomach pain
• Swelling of the face, lips, tongue and throat
• Tightness of the chest

Where to Buy Metronidazole in the UK

Metronidazole 400 mg tablets are classified as a prescription-only medication, so you’ll need to have approval from a clinician or doctor to obtain them. You can request them from trusted online services, such as Prescription Doctor, or you may be able to get them through the NHS. 

Can I Order Metronidazole Online?

Yes, you can order Metronidazole online from Prescription Doctor by following these steps:

• Complete a short questionnaire that details your lifestyle, medical history, and any other treatments you may be taking
• Order your preferred treatment 
• Your information is reviewed by our clinicians to determine whether the medication is suitable for you
• If approved, your order will be dispatched by our UK-based, General Pharmaceutical Council-registered dispensing pharmacy
• Should your order not be approved, our clinicians may recommend an alternative treatment

All orders approved before 3pm on a weekday are eligible for next-day delivery. Items are dispatched in plain packaging that does not reveal the contents. 

Can You Get Metronidazole Over the Counter in the UK?

No, it’s not possible to get Metronidazole 400 mg tablets over the counter in the UK. This is because the treatment is classified as a prescription-only antibiotic. The same applies if you prefer to receive the medication in gel form instead. 

Is Metronidazole on the NHS?

Yes, it is possible to get Metronidazole on the NHS; however, you will still need to make an appointment with your GP and obtain a prescription. They will use the same criteria as our clinicians, though it may take significantly longer to arrange an appointment with your doctor. 

Frequently Asked Questions (FAQs) About Metronidazole