Common questions about azathioprine - Brand name: Imuran

Azathioprine is a type of medicine called an immunosuppressant. These medicines work by suppressing or calming your immune system. This means your immune system becomes weaker.

If you take azathioprine for an inflammatory or autoimmune condition, it slows down the production of new cells in your body's immune system. This helps reduce the swelling (inflammation) that causes swollen and stiff joints in rheumatoid arthritis or damage to your bowel in Crohn's disease.

After a transplant, your body will try to attack the new organ as it does not recognise it. By suppressing your immune system, azathioprine helps stop your body rejecting a new organ.

Azathioprine is not a painkiller, but because it reduces the inflammation caused by conditions such as rheumatoid arthritis, you may have less pain.

Azathioprine starts to work gradually.

For inflammatory conditions such as rheumatoid arthritis and Crohn's disease, it can take up to 12 weeks of taking the right adjusted dose before you notice any benefits. For some skin conditions it can take several months or more.

It's important to keep taking azathioprine. You may not feel any different at first, however azathioprine is likely to be working.

If you take it after a transplant you will not notice any benefits from the medicine itself. However, as the transplanted organ begins to work, you'll usually begin to feel a lot better. Azathioprine will help to keep your new organ working properly.

Many people will take azathioprine for a long time. If you've had an organ transplant, you'll probably take it for the rest of your life.

You'll have regular blood tests while taking azathioprine. These blood tests will make sure that any concerns or problems are found quickly.

Taking azathioprine for a long time can increase your chance of getting certain types of cancer, including skin cancer. For this reason, avoid strong sunlight and use a sunscreen (SPF 30 or more), and wear clothes that cover your arms and legs.

Speak to your doctor if you're worried about long-term side effects.

Azathioprine affects your immune system and this can make you more likely to get an infection.

It's important to reduce your risk of getting an infection. When possible, avoid close contact with people who you know are unwell.

Tell your doctor if you think you're getting a sore throat, if you have a high temperature or if you have symptoms or test positive for coronavirus (COVID-19).

It's important to have any vaccinations that you're invited for. Tell the person giving the vaccine that you take azathioprine, as some types of vaccine may not be suitable for you.

People who live with you can reduce the risk of passing on an infection by also having vaccinations.

After an organ transplant you'll usually need a combination of medicines that suppress your immune system.

This combination will be adjusted gradually in the months after your operation. This depends on how well your new organ is working and whether you have any side effects from the medicines.

If you need more than one kind of immunosuppressant therapy or medicine, there's a risk that your immune system will become too weak.

For this reason, your doctor will prescribe the lowest level of therapy or lowest dose of medicine that works for you.

There are several different treatments that can help the symptoms of inflammatory conditions. These include medicines, other types of therapy and even surgery.

Your doctor will be able to recommend the best treatment for you, based on your condition and your symptoms.

Treatments for rheumatoid arthritis include:

• medicines such as methotrexate, biological medicines (made from proteins and other substances produced by the body) and steroids
• painkillers, including non-steroidal anti-inflammatory drugs (NSAIDs)
• supportive treatments, including physiotherapy
• surgery, including joint replacement
• complementary therapies, including acupuncture

Treatments for Crohn's disease include:

• steroids such as prednisolone
• immunosuppressants such as methotrexate
• biological medicines such as adalimumab
• surgery to remove an inflamed section of bowel
• a liquid diet (enteral nutrition), suitable for children and young adults

Treatments for severe eczema include:

• medicines such as methotrexate, biological medicines (made from proteins and other substances produced by the body) or baricitinib
• steroid creams that you put on your skin
• medicated bandages
• medicines called tacrolimus or pimecrolimus that you put on your skin
• phototherapy
• antihistamines
• painkillers such as non-steroidal anti-inflammatory drugs (NSAIDs)
• antifungal shampoos

Azathioprine does not affect any type of contraception, including the combined contraceptive pill, progestogen-only pill and emergency contraception.

If you're are being sick (vomiting) or have severe diarrhoea for more than 24 hours, your contraceptive pills may not protect you from pregnancy. Look on the pill packet to find out what to do.

Find out more:

• What to do if you're sick or have diarrhoea when taking the combined pill
• What to do if you're sick or have diarrhoea when taking the progestogen-only pill

Azathioprine will not usually affect you being able to drive or cycle.

If you get any symptoms that affect your ability to concentrate, do not drive or cycle until you feel better.

Alcohol does not affect the way azathioprine works. However, both azathioprine and alcohol can affect your liver.

For this reason it's even more important to stick to the national guidelines of drinking no more than 14 units of alcohol a week, spread across 3 or more days.

A medium glass of wine (175ml) is 2 units of alcohol. A pint of lager or beer is 2 to 3 units of alcohol.

Apart from limiting alcohol, you can eat and drink normally while taking azathioprine.

But do not take azathioprine at the same time as milk or dairy products, as this may lower the levels of azathioprine in your body. Take your tablets at least 1 hour before or 2 hours after having milk or dairy products.