A bile-acid sequestrant
Colesevelam
A bile-acid sequestrant that lowers cholesterol by binding bile acids in the gut; it must be taken well apart from other medicines.
What is Colesevelam?
Colesevelam is a bile-acid sequestrant used to help lower cholesterol, often alongside a statin or when a statin alone is not enough or not tolerated. It works in the gut, binding bile acids so the body makes more from cholesterol, which lowers blood cholesterol. Because it can bind other medicines and stop them being absorbed, other tablets are taken well apart from it.
Education and reference only. This is a plain-language guide to Colesevelam — 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
Colesevelam is a bile-acid sequestrant used in the UK to help lower cholesterol. It is usually added when a statin alone is not enough, or used when statins are not tolerated. Unlike most cholesterol medicines it is not absorbed into the body — it works entirely within the gut. It is taken regularly as a long-term medicine, and the main practical point is that it can bind other medicines in the gut, so timing matters.
How it works
Bile acids are made by the liver from cholesterol and released into the gut to help digest fat. Colesevelam binds to these bile acids in the gut so they are passed out rather than reabsorbed. To replace them, the liver uses up more cholesterol to make new bile acids, which lowers the amount of cholesterol in the blood. Because it grips substances in the gut, it can also bind other medicines and some vitamins, which is why timing and monitoring matter.
Company & origin
Originated / developed by: Developed by Genzyme; marketed in the UK by Genzyme/Sanofi..
Colesevelam is a bile-acid sequestrant introduced in the early 2000s and marketed in the UK as Cholestagel to help lower cholesterol.
What it treats
Conditions Colesevelam is used for
Practical use
How to take Colesevelam
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Take it regularly with a meal and a good drink of water, as advised.
- Take your other medicines well apart from it — usually well before or several hours after — as it can bind them and stop them being absorbed.
- Increase fibre and fluids to help reduce constipation, which is the most common side effect.
- Tell your prescriber if you take other medicines with a narrow margin, so timing can be planned.
- If you miss a dose, take it with your next meal — do not double up.
- Do not stop it on your own without advice, as your cholesterol may rise again.
Weighing it up
Advantages & disadvantages of Colesevelam
Advantages
- It works only in the gut and is not absorbed, so it can suit people who cannot take statins.
- It can be added to a statin to lower cholesterol further.
- It does not carry the muscle side effects associated with statins.
Disadvantages
- It can bind other medicines in the gut, so doses have to be carefully spaced.
- Constipation is common and can be troublesome.
- It can raise triglycerides (another blood fat), which need monitoring.
Practical use
Good to know
Colesevelam works in the gut and is not absorbed into the body, which can make it a useful option when statins are not tolerated, or as an add-on. Its main drawback is that it can bind other medicines in the gut and stop them working properly, so other tablets are usually taken well before or several hours after it — check the timing with your pharmacist. Constipation is the most common side effect, and it can raise triglycerides (another blood fat), so these are kept under review.
Who should not take it / use with caution
- People with a bowel or stomach blockage, or other significant bowel obstruction.
- People with very high triglyceride levels, as it can raise them further.
- People with swallowing difficulties or certain gut conditions, used with caution.
Monitoring
- Cholesterol blood tests to check the response.
- Triglyceride levels, which it can raise.
- Reviewing bowel symptoms such as constipation and the timing of other medicines.
Side effects
- Constipation.
- Wind, bloating and tummy discomfort.
- Nausea or indigestion.
- A rise in triglycerides (another blood fat) in some people.
Key interactions
- It can bind and reduce the absorption of many other medicines, so they are taken well apart from it.
- It can reduce absorption of some fat-soluble vitamins over time.
- Take particular care with medicines where the level matters closely, planning the timing with your pharmacist.
Available as: Tablets, and a powder to mix with liquid.
Answers
Colesevelam: frequently asked questions
Why must I space colesevelam from my other tablets?
Colesevelam binds substances in the gut, including other medicines, which can stop them being absorbed and working. Other tablets are usually taken well before or several hours after it — your pharmacist can help you plan the timing.
Does colesevelam cause constipation?
Yes, constipation is its most common side effect. Drinking plenty of fluids and eating more fibre can help. Tell your prescriber if it becomes troublesome.
Can colesevelam be used if I can't take statins?
Yes — because it works only in the gut and is not absorbed, it is sometimes used when statins are not tolerated, either on its own or with other cholesterol treatments.
Will colesevelam affect my triglycerides?
It can raise triglycerides (another blood fat) in some people, so these are checked. If your triglycerides are already high, it may not be the right choice.
How do I take the powder form?
The powder is mixed with liquid and taken with a meal, as directed. Follow the instructions from your pharmacist on how to mix and when to take it.
The wider class
About Bile-acid sequestrants
Colesevelam belongs to the bile-acid sequestrants 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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