Purified fish-oil esters for high triglycerides
Omega-3-acid ethyl esters
A purified fish-oil medicine used to lower high triglycerides, a type of blood fat.
What is Omega-3-acid ethyl esters?
Omega-3-acid ethyl esters are a purified, prescription form of the omega-3 oils found in fish, used to help lower high triglycerides, a type of fat in the blood. They are taken as capsules by mouth, usually with food. They are sometimes also used after a heart attack as part of a wider treatment plan. They work alongside, not instead of, a healthy diet and other treatments. They are different from ordinary fish-oil supplements because they are a standardised, regulated medicine, and they can interact with blood-thinning medicines.
Education and reference only. This is a plain-language guide to Omega-3-acid ethyl esters — 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
Omega-3-acid ethyl esters are a lipid-regulating medicine, meaning they help adjust the fats in the blood. They are a purified and concentrated form of the omega-3 fatty acids found naturally in oily fish, supplied as a regulated medicine under the brand Omacor rather than as an ordinary supplement. They are mainly used to help lower high triglycerides, a type of blood fat that, when raised, can add to heart and circulation risk. In some cases they are also used after a heart attack as part of a broader treatment plan. They are taken by mouth as capsules.
How it works
Triglycerides are a type of fat carried in the blood, and high levels can contribute to the risk of heart and circulation problems and, when very high, to inflammation of the pancreas. Omega-3-acid ethyl esters help by reducing the amount of triglycerides the body makes and carries, bringing high levels down. They are used alongside lifestyle measures such as a healthier diet, less alcohol and more activity, and often alongside other lipid medicines such as statins, which mainly target a different blood fat (cholesterol). Because they work gradually, they are taken regularly, usually with food, and blood fats are rechecked to see the effect.
Company & origin
Originated / developed by: Specialist manufacturer.
A purified, prescription form of fish-oil omega-3 used in the UK to help lower high blood fats called triglycerides.
Practical use
How to take Omega-3-acid ethyl esters
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Take the capsules by mouth with food, which helps absorption and reduces a fishy aftertaste or burping.
- Keep up the lifestyle changes you are advised, such as a healthier diet, less alcohol and more activity.
- Take it regularly as prescribed, as it works gradually to bring high triglycerides down.
- Tell your doctor if you take blood-thinning medicines, as omega-3 can add a mild blood-thinning effect.
- Go for the blood tests your doctor arranges so the effect on your blood fats can be checked.
Weighing it up
Advantages & disadvantages of Omega-3-acid ethyl esters
Advantages
- An effective, purified medicine for helping to lower high triglycerides.
- A regulated, standardised form rather than a variable over-the-counter supplement.
- Can be used as part of a wider plan, including after a heart attack in some cases.
Disadvantages
- Commonly causes a fishy aftertaste, burping or mild stomach upset.
- Can add a mild blood-thinning effect, which matters alongside anticoagulant or antiplatelet medicines.
- Works on triglycerides specifically and is used alongside, not instead of, diet and other treatments.
Practical use
Good to know
It helps to know that this is a regulated medicine and not the same as buying fish-oil capsules off the shelf, because the prescription form is purified and standardised. It works best alongside lifestyle changes, including a healthier diet, cutting back on alcohol and being more active, since these have a big effect on triglycerides. Take it with food, which improves how it is absorbed and reduces a fishy aftertaste or burping, the most common minor complaints. An important safety point is that omega-3 can have a mild blood-thinning effect, so tell your doctor if you take anticoagulant or antiplatelet medicines, and mention any bleeding tendency. Your doctor will recheck your blood fats to see how well it is working and may adjust the wider plan.
Who should not take it / use with caution
- People who have had a serious allergic reaction to omega-3 products, fish or soya should check with their doctor before use.
- It is used with care in people taking blood-thinning medicines or with a bleeding tendency.
- It is used with care in people with significant liver problems, under medical guidance.
- It is used in pregnancy only on the advice of a doctor.
Monitoring
- Rechecking blood fats, particularly triglycerides, to see how well it is working.
- Checking liver function where appropriate during treatment.
- Reviewing bleeding risk in people also taking blood-thinning medicines.
Side effects
- A fishy aftertaste or burping, which taking it with food can help.
- Mild stomach upset, nausea or indigestion.
- Occasionally, changes in some blood tests, such as liver tests.
- Rarely, an allergic-type reaction, which should be reported.
Key interactions
- It can add to the effect of blood-thinning medicines such as anticoagulants and antiplatelets, raising bleeding risk.
- It is often used alongside other lipid medicines such as statins, which target a different blood fat.
- Tell your doctor about all your medicines and supplements, including other fish-oil products.
Available as: Capsules taken by mouth.
Answers
Omega-3-acid ethyl esters: frequently asked questions
What are omega-3-acid ethyl esters used for?
They are a purified fish-oil medicine used mainly to help lower high triglycerides, a type of blood fat, and sometimes as part of a wider plan after a heart attack.
Are they the same as fish-oil supplements?
No. This is a purified, standardised prescription medicine, which is different from ordinary fish-oil capsules sold as supplements.
Why take them with food?
Taking the capsules with food helps your body absorb them and reduces the fishy aftertaste and burping that some people notice.
Do they thin the blood?
Omega-3 can have a mild blood-thinning effect, so tell your doctor if you take anticoagulant or antiplatelet medicines or have a bleeding tendency.
Do they replace a healthy diet?
No. They work alongside lifestyle measures such as a healthier diet, less alcohol and more activity, which have a big effect on triglycerides.
Authoritative sources
- BNF
- NICE CKS
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