METRONIDAZOLE TABLETS BP 400MG
Active substance(s): METRONIDAZOLE
Read all of this leaflet carefully before you start taking this medicine.
• Keep this leaflet. You may need to read it again.
• If you have any further questions, ask your doctor or pharmacist.
• This medicine has been prescribed for you.
Do not pass it on to others. It may harm them, even if their symptoms are the same as
What Metronidazole tablets are and what they are used for
Before you take
How to take
Possible side effects
How to store
What Metronidazole tablets are and what they are used for
Metronidazole tablets belong to a group of medicines called anti-infective agents.
They may be used to treat:
• infections, caused by bacteria of the blood, brain, bone, lung, stomach lining and
pelvic area, following childbirth or in a wound following an operation
• urinary or genital infections caused by a parasite, Trichomonas
• genital infection in women caused by bacteria
• the parasitic diseases amoebiasis
• the disease giardiasis
• gum and teeth infections
• infected leg ulcers or pressure sores
• stomach ulcers caused by Helicobacter pylori.
• or prevent infections occurring after operations.
Before you take
Do not take Metronidazole tablets and tell your doctor if you:
• are allergic (hypersensitive) to Metronidazole tablets or any of the other
ingredients (see section 6)
• are in the first 3 months of pregnancy or are breastfeeding.
Check with your doctor or pharmacist before taking Metronidazole tablets if you:
• have kidney disease, particularly if you require dialysis treatments
• are or have ever suffered from any liver disease
• are in the 4th-9th month of pregnancy
• have epilepsy or have ever had fits
• have porphyria (a genetic disease that can cause skin blisters, abdominal pain and
brain/nervous system disorders)
• have any disorder of the blood and/or blood cells
• have any nervous system disorders
• have been exposed to any sexually transmitted disease.
Warnings and precautions
Cases of severe liver toxicity/acute liver failure, including cases with a fatal outcome,
in patients with Cockayne syndrome have been reported with product containing
If you are affected by Cockayne syndrome, your doctor should also monitor your
liver function frequently while you are being treated with metronidazole and
Tell your doctor immediately and stop taking metronidazole if you develop:
• Stomach pain, anorexia, nausea, vomiting, fever, malaise, fatigue, jaundice, dark
urine, putty or mastic coloured stools or itching.
Taking other medicines
Please tell your doctor or pharmacist if you are taking or have recently taken any
other medicines, including medicines obtained without a prescription. Especially:
• medicines to stop the blood clotting such as warfarin
• lithium (used to treat depression)
• medicines to treat epilepsy such as phenobarbital, phenytoin, primidone
• disulfiram (to treat alcohol addiction)
• ciclosporin (used following organ transplants)
• fluorouracil (used to treat some forms of cancer)
• cimetidine (used to treat stomach ulcers)
• oestrogen contraceptives (‘the pill’).
Pregnancy and breastfeeding
Metronidazole tablets must not be taken during the first 3 months of pregnancy and
should not be taken during the rest of the pregnancy.
If you breastfeed you should stop whilst taking Metronidazole tablets and for 1224 hours after the course of tablets has finished before breastfeeding again.
Ask your doctor or pharmacist for advice before taking this medicine.
Driving and using machines
Metronidazole tablets may make you feel drowsy, dizzy, confused or affect your
vision, cause fits or hallucinations. Make sure you are not affected before you drive,
operate machinery or take part in any activities where these may put you or others at
If you have been told you have an intolerance to some sugars, contact your doctor
before taking this medicine, as it contains a sugar called lactose.
If you are taking this medicine for more than 10 days, your doctor may wish to carry
out further tests.
If you need any blood or urine tests, tell your doctor you are taking Metronidazole
tablets before the test.
How to take
Always take Metronidazole tablets exactly as your doctor has told you. If you are not
sure, check with your doctor or pharmacist.
You are advised not to drink alcohol whilst taking this medicine and for 48 hours
after finishing the course of tablets, as this might cause unpleasant side-effects, such
as feeling or being sick, stomach pain, hot flushes, palpitations and headache.
Swallow the tablets whole, during or after meals, with a glass of water. Do not
• Treatment of bacterial infections
Adults and children over 10 years: 800mg followed by 400mg at eight hourly
intervals. Treatment is usually for 7 days but will depend upon your condition.
• Treatment of anaerobic infections
Children 8 weeks-12 years: 20-30mg/kg/day as a single dose or divided into 7.5mg/kg
every 8 hours for 7 days.
Children under 8 weeks: 15mg/kg/day as a single dose or divided into 7.5mg/kg every
• Treatment of infection caused by Trichomonas
Adults and adolescents: 2g as a single dose, or 200mg three times a day for 7 days, or
400mg twice a day for 5 to 7 days.
Your partner should also be treated.
Children under 10 years: 40mg/kg as a single dose or 15-30mg/kg/day two to three
times daily for 7 days.
• Treatment of non-specific genital infection in women
Women: 400mg twice a day for 7 days, or 2g as a single dose for 1 day only.
Adolescent girls: 400mg twice daily for 5 to 7 days or 2g as a single dose.
• Treatment of amoebiasis
Adults and children over 10 years: 400mg-800mg three times a day for 5 to 10 days.
Children 7-10 years: 200mg-400mg three times a day for 5 to 10 days.
Children 3-7 years: 100mg-200mg four times daily for 5 to 10 days.
Children 1-3 years: 100mg-200mg three times daily for 5 to 10 days.
Or 35-50mg/kg/day in 3 divided doses for 5 to 10 days.
• Treatment of giardiasis
Adults and children over 10 years: 2g once a day for 3 days, or 400mg three times a
day for 5 days or 500mg twice daily for 7-10 days.
Children 7-10 years: 1g once a day for 3 days.
Children 3-7 years: 600mg-800mg once daily for 3 days.
Children 1-3 years: 500mg once daily for 3 days.
Or 15-40mg/kg/day divided in two to three doses
• Treatment of infections of the gums (for 3 days) or teeth (for 3-7 days)
Adults and children over 10 years: 200mg three times a day
• Treatment of infected leg ulcers or pressure sores (for 7 days)
Adults and children over 10 years: 400mg three times a day
• Treatment of stomach ulcers caused by Helicobacter pylori
To be taken as directed by your doctor as part of a course with two other medicines.
• Prevention of infections after surgery
Adults: 1g as a single dose 24 hours before surgery then, 400mg at 8 hourly intervals
during the 24 hours before the operation.
Children under 12 years: 20-30mg/kg as a single dose 1-2 hours before the operation.
Newborns with a gestation age less than 40 weeks: A more suitable dosage form
should be used.
If you are elderly or have liver disease, it is particularly important to take this
medicine exactly as directed by the doctor.
If you take more than you should
If you (or someone else) swallow a lot of tablets at the same time, or you think a child
may have swallowed any contact your nearest hospital casualty department or tell
your doctor immediately. Signs of an overdose include feeling or being sick, loss of
appetite, diarrhoea, metallic taste, headache, dizziness, insomnia or drowsiness.
If you forget to take the tablets
Do not take a double dose to make up for a forgotten dose. If you forget to take a dose
take it as soon as you remember it and then take the next dose at the right time.
If you stop taking the tablets
If you stop taking the tablets your infection may come back. Talk to your doctor
before you stop taking the tablets and follow their advice.
Possible side effects
Like all medicines, Metronidazole tablets can cause side effects, particularly when
you first start taking it, although not everybody gets them. Please tell your doctor or
pharmacist if you notice any of the following effects or any effects not listed.
Contact your doctor at once if you notice any of the following side effects:
• Allergic reactions: skin rash, which may be itchy, swelling of the face, lips,
tongue or throat, fever or difficulty in breathing.
Tell your doctor if you notice any of the following side effects or notice any other
effects not listed:
Very rare (less than 1 in 10,000 users):
• increased bruising, nosebleeds, sore throats or infections, this medicine may
alter the numbers and types of your blood cells. You should tell your doctor
who might want you to have a blood test
• mental health problems including hallucinations (seeing or hearing things that
are not there), drowsiness, dizziness, fits, tingling, pain or a feeling of weakness
in the arms or legs, numbness
• encephalopathy (headaches, light sensitivity, confusion, fever, paralysis, stiff
• cerebellar syndrome (poor co-ordination or muscle control, involuntary
shakiness, uncontrolled eye movements, speech disorders, walking abnormally)
• double vision, short sightedness
• change in liver function tests, jaundice (yellowing of the skin or whites of the
eyes), inflammation of the pancreas (pancreatitis causing very severe abdominal
• skin rashes, itching, small pus-containing blisters, muscles and joint pain,
darkening of the urine
Not known (cannot be estimated from the available data):
• bone marrow depression disorders such as aplastic anaemia (causing weakness,
bruising, making infections more likely)
• Urticaria (itchy, pale or red irregular raised patches of skin), fever
• depression, ‘pins and needles’
• unpleasant taste in the mouth, changes in taste, furred tongue, mouth ulcers,
feeling or being sick, loss of appetite, diarrhoea, stomach pain and upset
• erythema multiforme (circular, irregular red patches)
Reporting of side effects
If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any
possible side effects not listed in this leaflet. You can also report side effects directly
via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard
By reporting side effects you can help provide more information on the safety of this
How to store
Keep out of the reach and sight of children.
Store below 25°C in a dry place.
Do not use Metronidazole tablets after the expiry date stated on the
label/carton/bottle. The expiry date refers to the last day of that month.
Medicines should not be disposed of via wastewater or household waste. Ask your
pharmacist how to dispose of medicines no longer required. These measures will help
to protect the environment.
What Metronidazole tablets contain
• The active substance (the ingredient that makes the tablets work) is metronidazole.
• The other ingredients are croscarmellose sodium, cellulose, colloidal silica, lactose,
magnesium stearate, maize starch, polyethylene glycol, titanium dioxide (E171),
hydroxypropylcellulose (E463), methylhydroxypropylcellulose (E464).
What Metronidazole tablets look like and contents of the pack
Metronidazole 200mg tablets are white, film-coated tablets.
Metronidazole 400mg tablets are white, capsule shaped, biconvex, film-coated tablets.
Pack sizes are 21 tablets
Marketing Authorisation Holder and Manufacturer
Actavis, Barnstaple, EX32 8NS, UK.
Date of last revision: December 2016
Source: Medicines and Healthcare Products Regulatory Agency
Disclaimer: Every effort has been made to ensure that the information provided here is accurate, up-to-date and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. This information has been compiled for use by healthcare practitioners and consumers in the United States. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate that the drug or combination is safe, effective or appropriate for any given patient. If you have questions about the substances you are taking, check with your doctor, nurse or pharmacist.