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Active substance(s): CIMETIDINE

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Tagamet 400 mg Tablets
Read all of this leaflet carefully before you start using 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 yours.
• If any of the side effects get serious, or if you notice any side effects not listed in this
leaflet, please tell your doctor or pharmacist.
In this leaflet:
1. What this medicine is and what it is used for
2. Before you take
3. How to take
4. Possible side effects
5. How to store
6. Further information
1. What this medicine is and what it is used for
Tagamet tablets contain cimetidine which is a histamine H2 antagonist. It helps to reduce the
natural production of acid in the stomach.
They are used to treat and relieve:
• the symptoms of peptic ulcers which occur in the stomach or intestine (gut)
• oesophageal reflux disease which can be caused when food and acid from the stomach
washes back into the food pipe (oesophagus). This can cause a burning feeling in the
chest known as heartburn
• a rare condition called Zollinger-Ellison syndrome when the stomach produces very
large amounts of acid.
This medicine may also be prescribed for a range of other medical conditions where a
reduction of acid production in the stomach is needed, or to protect your stomach from other
medicines (such as non-steroidal anti-inflammatories).
2. Before you take
Do NOT take Tagamet tablets if you:
• are allergic to cimetidine or to any of the other ingredients (see Section 6).
If this applies to you, speak to your doctor or pharmacist.


Take special care with Tagamet tablets
Before taking the tablets, tell your doctor if you:
• have a kidney problem
• have a blood disease
• have had a peptic ulcer and are also taking a non-steroidal anti-inflammatory drug
(NSAID), (e.g. ibuprofen)
• are pregnant or planning a pregnancy
• are breast-feeding.
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, and herbal preparations.
Some medicines may be affected by Tagamet or they may affect how well Tagamet will
work. Tell your doctor or pharmacist if you are taking medicines which:
• control epilepsy (e.g. phenytoin). Your doctor will monitor you
• thin the blood (e.g. warfarin). Your doctor will monitor you
• treat breathing problems (e.g. theophylline)
• may cause your blood cell count to change (e.g. antibiotics)
• treat fungal (yeast) infections (e.g. ketoconazole, itraconazole, posaconazole)
• treat diabetes (e.g. glipizide, metformin)
• treat anxiety (e.g.diazepam)
• treat depression, called tricyclic antidepressants (e.g. amitriptylline)
• lower blood pressure or treat heart conditions (e.g. metoprolol, propranolol,
nifedipine, diltiazem, procainamide)
• numb the body such as anaesthetics used in hospital (e.g. lidocaine)
• are strong pain relievers (e.g.morphine)
• suppress the immune system (e.g. ciclosporin, tacrolimus)
• treat HIV/AIDS (e.g. atazanavir)
• treat tumours or cancer (e.g. carmustine, fluorouracil, epirubicin), or if you are having
radiation therapy.
Pregnancy and breast-feeding
DO NOT take Tagamet if you are pregnant, planning to become pregnant or breast-feeding
unless advised to by your doctor.
Ask your doctor for advice before taking any medicine.
Driving and using machines
Tagamet tablets are unlikely to affect your ability to operate machinery or to drive.
Important information about some of the ingredients of Tagamet tablets
• sodium
The sodium content per tablet is:
400 mg tablet - 1 mg
This should be taken into consideration by patients on a controlled sodium diet.


3. How to take
Always take Tagamet tablets exactly as your doctor has told you and always read the label.
Your doctor will decide on the appropriate dose to suit your condition. Ask your doctor or
pharmacist if you are not sure.

Swallow the tablets whole with a drink of water. Take the tablets with meals or at
bedtime as advised by your doctor.

Adults and the elderly: the usual dose is 400 mg twice a day with breakfast, and at bedtime.
Your doctor will tell you the correct dose depending on your condition.
The maximum dose is 2400 mg a day.
Children: your doctor will decide on the dose according to your child's body weight.
The usual length of treatment is at least four weeks though this may be longer in some
conditions. Your doctor will advise you.
If you take more than you should
1. Tell your doctor, pharmacist or nearest hospital casualty department immediately.
2. Take the container and any remaining tablets with you so that people can see what you
have taken.
3. Do this even if you feel well.
If you forget to take
If you forget to take a dose take it as soon as you remember, but if it is almost time for your
next dose, skip the missed dose and continue as usual.
Do not use a double dose to make up for a missed dose.
If you stop taking
If you stop your treatment too soon, your symptoms may come back.
You may feel better after a few days, but you should keep taking your medicine until the
prescribed course is finished.
If you have any further questions on the use of this product, ask your doctor or pharmacist.
4. Possible side effects
Like all medicines, Tagamet tablets can cause side effects, although not everybody gets them.
Do not be alarmed by this list of possible side effects. You may not experience any of them.


STOP taking the tablets and seek medical help immediately if you have any of the
following allergic reactions:
• difficulty breathing or swallowing, swelling of the face, lips, tongue or throat
• severe itching of the skin, with a red rash or raised lumps.
Seek immediate medical attention if you have any of the following symptoms:
• unusual bleeding or bruising; or fever, sore throat, mouth ulcers, repeated infections
or infections that will not go away. This may be due to changes in your blood
• red spots on the skin which may be painful to touch, joint pain, swollen lymph glands
• yellowing of your skin or eyes, pale faeces and dark urine, unexplained persistent
nausea, stomach problems, loss of appetite or unusual tiredness. This may be due to
liver changes
• confusion, hallucinations, depression
• in men: enlarged breasts, trouble getting or keeping an erection
• unexpected secretion of breast milk in men or women
• pain behind the ribs radiating towards the back, often worse when lying down, nausea,
vomiting, fever. This may be due to inflammation of the pancreas
• unusually slow or fast heartbeat, irregular heartbeat and fainting
• fever, rash, nausea, aches and pains, change in colour of urine, passing more or less
urine than usual or passing urine at night. These problems may indicate kidney
• aching or weak muscles, or aching joints.
Tell your doctor if you get any of the following side effects:
• diarrhoea
• dizziness
• tiredness
• mild skin rash
• headache
• hair loss.
Side effects with Tagamet tablets are usually mild and do not last long.
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 (see
details below). By reporting side effects you can help provide more information on the safety
of this medicine.
Yellow Card Scheme
5. How to store

Keep out of the reach and sight of children.
Do not take after the expiry date which is stated on the blisters and on the carton. The
expiry date refers to the last day of that month.
Do not store above 25ºC. Store in the original package.


Do not throw it away with your household waste or in water. Return all the unwanted
medicine to your pharmacist. This will help to protect the environment.

6. Further information
What Tagamet Tablets contain
• The active ingredient is cimetidine (400 mg).
• The other ingredients are:
microcrystalline cellulose, povidone K30, sodium starch glycollate, sodium
laurilsulfate, colloidal anhydrous silica, magnesium stearate, macrogol 400,
hypromellose, and the colours titanium dioxide, quinoline yellow aluminium lake,
indigo carmine aluminium lake and iron oxide yellow. (See end of Section 2 for
further information on sodium).
What Tagamet Tablets look like and contents of the pack
• Tagamet 400 mg Tablets are pale green, oblong, film-coated tablets, marked with
'Tagamet' on one side and '400' on the reverse. They are available in packs of 56, 60,
100, 250, 500 or 1000.*
*Not all pack sizes may be marketed.
Marketing Authorisation Holder
Chemidex Pharma Ltd, trading as Essential Generics, 7 Egham Business Village, Crabtree
Road, Egham, Surrey TW20 8RB.
Dales Pharmaceuticals Ltd, Snaygill Industrial Estate, Keighley Road, Skipton, North
Yorkshire, BD23 2RW.
This leaflet was last revised in
April 2015
'Tagamet' and 'Chemidex' are trade marks.


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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.