Can I take Cod liver oil and Doxadura together?

It is usually safe to take cod liver oil and doxadura (doxazosin) together, but you should monitor your blood pressure regularly.

To avoid dizziness, get up slowly from a sitting or lying position. If you feel very dizzy, faint, or notice unusual bruising, speak to your doctor or pharmacist. They may want to adjust your dose or check your blood pressure more frequently.

Why this happens

Doxazosin works by relaxing blood vessels to lower blood pressure. Cod liver oil contains omega-3 fatty acids, which also have a natural, mild blood-pressure-lowering effect. When used together, these effects can add up (an additive effect).

Cod liver oil also slightly reduces the ability of blood cells (platelets) to stick together, which can affect clotting.

How to know if you're having a drug interaction

You may be experiencing an interaction between cod liver oil and doxadura if:

• You feel dizzy or lightheaded, especially when standing up.

• You experience fainting or near-fainting episodes.

• You notice unusual bruising or bleeding.

• You develop headaches or flushing.

• You feel unusually tired or weak.

• Symptoms start after starting cod liver oil or increasing the dose while taking doxazosin.

What you should do

If you have any of the above symptoms, you should:

• Speak to your GP or pharmacist for advice as soon as possible.

• Do not stop taking doxazosin suddenly unless advised by a healthcare professional.

• Avoid starting, stopping, or changing cod liver oil without medical advice.

• Seek urgent medical help if you faint or have heavy or persistent bleeding.

• Attend any blood pressure checks arranged to monitor your treatment.

Important precautions

First-dose hypotension

Doxadura can cause a sudden drop in blood pressure when you first start taking it or when the dose is increased. Take your first dose at bedtime to avoid dizziness or fainting.

Pregnancy

Do not take cod liver oil if you are pregnant or planning to become pregnant. It contains high levels of Vitamin A (retinol), which can harm the development of an unborn baby.

Cataract surgery

If you are due to have eye surgery for cataracts, you must tell your surgeon you are taking doxadura. It can cause a complication called 'Floppy Iris Syndrome' which the surgeon needs to prepare for.

Food and drink warnings

Alcohol

It is best to avoid or strictly limit alcohol while taking Doxadura. Alcohol can increase the blood-pressure-lowering effect of this medicine, which may make you feel dizzy, lightheaded, or faint, especially when standing up.

It is best to avoid or strictly limit alcohol when taking cod liver oil. Both alcohol and high doses of vitamin A (found in cod liver oil) can put strain on the liver; combining them may increase the risk of liver toxicity.

Using other medicines

Taking multiple medicines? Our Medicines Interaction Checker helps you check whether your prescriptions, over-the-counter medicines, and supplements are safe to take together. Simply search for your medicines to see potential interactions and what to do about them.

Disclaimer

This information is for general educational purposes only and should not be relied upon as a substitute for professional medical advice. Always consult your GP, pharmacist, or another qualified healthcare professional before making decisions about your medications. Individual circumstances may vary, and only a healthcare professional who knows your medical history can provide personalised guidance.