Health Centres - Tagamet (cimetidine)
How does it work?
Tagamet tablets and syrup contain the active ingredient cimetidine, which is a type of medicine called an H
Cimetidine works by blocking H
Stomach acid is produced in the stomach as a normal part of the digestive process. Normally the linings of the stomach and duodenum (an area of the intestine directly after the stomach) are protected by a layer that resists acid attack. However, if this layer is damaged, or large amounts of stomach acid are formed, an ulcer can develop on the lining of the stomach or duodenum. This is called a peptic ulcer.
Acid produced in the stomach can also sometimes flow back into the food pipe (oesophagus). This is called gastro-oesophageal reflux, and can cause pain and a burning sensation known as heartburn. It can also irritate and damage the lining of the oesophagus, causing a condition called reflux oesophagitis.
By reducing the production of stomach acid cimetidine can be used to treat all these and other conditions. It stops excess acid flowing back into the foodpipe and can be used to relieve heartburn symptoms associated with acid reflux. It also allows the oesophagus to heal in reflux oesophagitis.
By reducing the amount of acid in the stomach and duodenum cimetidine also allows peptic ulcers to heal, and prevents them from recurring. It also relieves the symptoms of indigestion caused by excess stomach acid.
Cimetidine can be used to prevent and treat peptic ulcers that can occur as a side effect of non-steroidal anti-inflammatory drugs (NSAIDs), such as diclofenac. In addition it can relieve side effects such as indigestion that can be associated with these medicines.
Cimetidine is also used to depress stomach acid production in various other conditions. It is used in varying doses and for varying lengths of time depending on the condition being treated.
What is it used for?
- Prevention, treatment and relief of symptoms of peptic ulcers or indigestion associated with non-steroidal anti-inflammatory drugs (NSAIDs)
- Preventing bleeding from stress ulceration in the gut in people who are critically ill in intensive care
- Gastro oesophageal reflux disease
- Persistant indigestion symptoms related to excess stomach acid
- Excessive secretion of stomach acid due to a tumour or enlargement of the pancreas (Zollinger-Ellison syndrome)
- Preventing inhalation of acid from the stomach (acid aspiration) whilst under general anaesthetic
- Preventing inhalation of acid from the stomach (acid aspiration) in pregnant women during labour
- Preventing the breakdown of pancreatic enzyme supplements (pancreatin) given in the treatment of conditions such as cystic fibrosis and chronic pancreatitis
- Preventing malabsorption and fluid loss in short bowel syndrome.
Warning!
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Stomach cancer can have similar symptoms to stomach ulcers, and these symptoms can be relieved by cimetidine. For this reason, if it is suspected that you have a stomach ulcer, your doctor should exclude the possibility of stomach cancer before you start treatment with this medicine. Otherwise, this medicine could mask the symptoms of stomach cancer and therefore delay diagnosis of this condition. This is particularly important if you are middle aged or older and have new or recently changed symptoms.
- A large study has recently suggested that elderly people and people with diabetes, chronic lung disease, or an underactive immune system (for example due to treatment such as chemotherapy or radiotherapy, or diseases such as HIV) may have a higher risk of developing pneumonia while they are taking H
Use with caution in
- Decreased kidney function.
Not to be used in
- Allergy to any ingredient.
This medicine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy.
Pregnancy and breastfeeding
Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.
- The manufacturer recommends that this medicine should be avoided during pregnancy unless considered essential by your doctor. Seek medical advice.
- This medicine passes into breast milk. The manufacturer recommends that it should not be used by breastfeeding mothers unless considered essential by your doctor.
Side effects
Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.
- Diarrhoea
- Dizziness
- Rash
- Tiredness
- Abnormal enlargement of breasts in men (gynaecomastia)
- Depression
- Confusion
- Headache
- Pain in the muscles or joints
- Acute pancreatitis
- Blood disorders
- Liver disorders
The side effects listed above may not include all of the side effects reported by the drug's manufacturer.
