A medicine that protects the gut lining
Sucralfate
A mucosal protectant that forms a protective coating over ulcers and damaged areas, shielding them from acid so they can heal.
What is Sucralfate?
Sucralfate is a medicine that protects the lining of the stomach and gut. It forms a protective coating over ulcers and damaged areas, shielding them from acid so they can heal. It needs to be taken apart from other medicines and antacids, as it can stop them being absorbed, and it is used with care in kidney problems because it contains aluminium.
Education and reference only. This is a plain-language guide to Sucralfate — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Sucralfate is a mucosal-protectant medicine used to help protect and heal ulcers and damaged areas in the stomach and upper gut. Rather than reducing acid like a proton pump inhibitor, it works by forming a physical protective layer over the damaged tissue. It is used in the UK for conditions such as peptic ulcers and to protect a stressed or inflamed gut lining.
How it works
Sucralfate reacts with the acid in the stomach to form a sticky, paste-like substance that clings to ulcers and damaged areas. This forms a protective barrier that shields the raw tissue from stomach acid, digestive enzymes and bile, giving the ulcer a chance to heal. It works locally in the gut rather than being absorbed into the body in any significant amount.
Company & origin
Originated / developed by: A long-established mucosal protectant.
An ulcer-protecting medicine used in the UK to coat and shield areas of damage in the stomach and gut.
What it treats
Conditions Sucralfate is used for
Practical use
How to take Sucralfate
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- It is usually taken before meals on an empty stomach so it can coat the gut lining.
- Take other medicines at a different time, separated by a couple of hours, as sucralfate can block their absorption.
- Do not take antacids at the same time as sucralfate, as they can stop it working; space them apart.
- Drink plenty of fluids, as it can occasionally cause constipation.
- If you miss a dose, take it before your next meal as usual and do not double up.
Weighing it up
Advantages & disadvantages of Sucralfate
Advantages
- Protects and heals ulcers by coating them rather than by changing the whole body's acid.
- Acts locally in the gut and is barely absorbed into the body.
- Useful for protecting a damaged or stressed gut lining.
Disadvantages
- Can stop other medicines and antacids being absorbed unless they are spaced apart.
- Contains aluminium, so it is used with caution in kidney impairment.
- Constipation is a common nuisance effect.
Practical use
Good to know
Sucralfate works best on an empty stomach, usually taken before meals, so it can stick to the gut lining. It can bind to other medicines in the gut and stop them being absorbed, so other tablets should be taken at a different time, often a couple of hours apart. It also should not be taken at the same time as antacids, which can stop it working. Because it contains aluminium, it is used with caution in people with kidney problems, where aluminium can build up.
Who should not take it / use with caution
- Used with caution in people with kidney impairment because it contains aluminium, which can build up.
- Care is needed in critically ill people who are tube-fed, as it can form blockages.
- Used with caution in pregnancy and breastfeeding; discuss with your prescriber.
Monitoring
- Whether ulcer symptoms and healing improve over the treatment course.
- Kidney function in people at risk, because of the aluminium content.
- Bowel habit, as constipation is common, and the timing of other medicines.
Side effects
- Constipation is the most common effect; drinking plenty of fluids can help.
- Sometimes a dry mouth, nausea, indigestion or a bloated feeling.
- Rarely, a build-up of aluminium in people with poor kidney function, or an allergic reaction.
Key interactions
- It can bind many other medicines in the gut and stop them being absorbed — it is especially important to separate it in time from certain antibiotics (such as ciprofloxacin), thyroid medicine (levothyroxine), some epilepsy medicines (such as phenytoin) and digoxin.
- Antacids should not be taken at the same time, as they can stop sucralfate working.
- Tell your pharmacist about everything you take so doses can be spaced correctly.
Available as: Tablets and an oral suspension (liquid).
Answers
Sucralfate: frequently asked questions
How is sucralfate different from a PPI?
A proton pump inhibitor reduces stomach acid throughout the body. Sucralfate works locally by forming a protective coating over the ulcer, shielding it so it can heal.
Can I take my other tablets at the same time?
No. Sucralfate can stop other medicines being absorbed, so take them at a different time, usually a couple of hours apart. Ask your pharmacist about timing.
Can I use it with an antacid?
Not at the same time. Antacids can stop sucralfate working, so leave a gap between them if you need both.
Is it safe if I have kidney problems?
It is used with caution in kidney impairment because it contains aluminium, which can build up. Tell your prescriber if you have kidney problems.
When should I take it?
It is usually taken before meals on an empty stomach so it can coat the gut lining. Follow the directions on your prescription.
The wider class
About Mucosal-protectant / ulcer-healing medicines
Sucralfate belongs to the mucosal-protectant / ulcer-healing medicines class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
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Authoritative sources
- BNF
- NICE CKS
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