Cancer drugs A to Z list
Lenalidomide is a type of cancer drug. You pronounce it as len-uh-lid-oh-mide.
It is a treatment for myeloma and myelodysplastic syndromes (MDS).
You have lenalidomide on its own or with other cancer drugs. This page is about having lenalidomide on its own. Some people may have lenalidomide on its own after a stem cell transplant. This is called maintenance treatment.
Lenalidomide works in different ways. It:
interferes with chemicals that cells use to signal to each other to grow
helps the immune system to attack the cancer cells
blocks the growth of new blood vessels, which cancer cells need to be able to grow
You take lenalidomide as capsules. You swallow them whole with a glass of water. You take them at the same time each day.
You can take the capsules with or without food.
You should take the right dose, not more or less.
Talk to your healthcare team before you stop taking a cancer drug or if you miss a dose.
You have lenalidomide as . This means that you have the drug and then a rest to allow your body to recover.
Each cycle lasts 4 weeks.
You usually take lenalidomide once a day for 3 weeks and then have a break for 1 week. This is one cycle of treatment. You then start the next cycle.
You generally take it for as long as the treatment is working and the side effects aren’t too bad.
You have blood tests before and during your treatment. They check your levels of and other substances in the blood. They also check how well your liver and kidneys are working.
Before treatment starts you may have a blood test to check for viruses such as hepatitis B, hepatitis C, and HIV. This is called a viral screen.
It’s important for your doctor to know if you have had any of these viruses. This is because this treatment can weaken your and can cause the virus to become active again (reactivation).
Side effects can vary from person to person. They also depend on what other treatments you're having.
Your doctor, nurse or pharmacist will go through the possible side effects. They will monitor you during treatment and check how you are at your appointments. Contact your advice line as soon as possible if:
you have severe side effects
your side effects aren’t getting any better
your side effects are getting worse
Early treatment can help manage side effects better.
We haven't listed all the side effects here. Talk to your healthcare team if you have any new symptoms that you think might be a side effect of your treatment.
Remember it is very unlikely that you will have all of these side effects. But you might have some of them at the same time.
These side effects happen in more than 10 in 100 people (more than 10%). You might have one or more of them. They include:
Increased risk of getting an infection is due to a drop in . Symptoms include a change in temperature, aching muscles, cough, headaches, feeling cold and shivery, pain or a burning feeling when peeing or generally feeling unwell. You might have other symptoms depending on where the infection is.
Infections can sometimes be life threatening. You should contact your advice line urgently if you think you have an infection.
You might be breathless and look pale due to a drop in . This is called anaemia.
This is due to a drop in the number of platelets in your blood. These blood cells help the blood to clot when we cut ourselves. You may have nosebleeds or bleeding gums after brushing your teeth. Or you may have lots of tiny red spots or bruises on your arms or legs. This is known as petechiae.
You might feel very tired and as though you lack energy.
Various things can help you to reduce tiredness and cope with it, for example exercise. Some research has shown that taking gentle exercise can give you more energy. It is important to balance exercise with resting.
Skin problems include a skin rash, dry skin and itching. This usually goes back to normal when your treatment finishes. Your healthcare team can tell you what products you can use on your skin to help.
You may have a serious skin reaction, such as peeling or blistering of the skin. Contact your doctor straight away if you have any serious skin reaction while on treatment.
Numbness or tingling in fingers or toes is often temporary and can improve after you finish treatment. Tell your healthcare team if you're finding it difficult to walk or complete fiddly tasks such as doing up buttons.
Feeling or being sick is usually well controlled with anti sickness medicines. It might help to avoid fatty or fried foods, eat small meals and snacks and take regular sips of water. Relaxation techniques might also help.
It is important to take anti sickness medicines as prescribed even if you don’t feel sick. It is easier to prevent sickness rather than treat it once it has started.
You might have liver changes that are usually mild and unlikely to cause symptoms. They usually go back to normal when treatment finishes.
You have regular blood tests to check for any changes in the way your liver is working.
Tell your doctor or nurse if you have this. They can check for the cause of the pain and give you medicine to help.
is easier to sort out if you treat it early. Drink plenty and eat as much fresh fruit and vegetables as you can. Try to take gentle exercise, such as walking. Tell your healthcare team if you think you are constipated. They can give you a laxative if needed.
Contact your advice line if you have diarrhoea. For example, in one day you have 2 or more loose bowel movements than usual. If you have a , you might have more output than normal. Your doctor may give you anti diarrhoea medicine to take home with you after treatment.
Try to eat small meals and snacks regularly. It’s best to try to have a healthy balanced diet if you can. You don’t necessarily need to stop eating foods that contain . But if your diet is normally very high in fibre, it might help to cut back on high fibre foods such as beans, nuts, seeds, dried fruit, bran and raw vegetables.
Drink plenty to try and replace the fluid lost. Aim for 8 to 10 glasses per day.
This treatment might cause muscle spasms. Let your treatment team know and they can give you medicines to help.
You might develop a cough or breathing problems. This could be due to infection, such as pneumonia and bronchitis.
Tell your healthcare team straightaway if you get a high temperature. Ask them if you can take paracetamol to help lower your temperature.
A low level of potassium in the blood is called hypokalaemia. You have regular blood tests to check for this.
These side effects happen in between 1 and 10 out of every 100 people (between 1 and 10%). You might have one or more of them. They include:
blood clots that can be life threatening; signs are pain, redness and swelling where the clot is. Feeling breathless can be a sign of a blood clot in the lung. Contact your advice line or doctor straight away if you have any of these symptoms
sepsis - a serious reaction to an infection. Signs can include feeling very unwell, not passing urine, slurred speech or confusion, breathlessness, mottled or discoloured skin, extreme shivering or muscle pain. Call 999 or go to accident and emergency (A&E) immediately if you have any of these symptoms
pain in bones, joints or muscles
We have more information about side effects and tips on how to cope with them.
Cancer drugs can interact with medicines, herbal products, and some food and drinks. We are unable to list all the possible interactions that may happen. An example is grapefruit or grapefruit juice which can increase the side effects of certain drugs.
Tell your healthcare team about any medicines you are taking. This includes vitamins, herbal supplements and over the counter remedies. Also let them know about any other medical conditions or allergies you may have.
Lenalidomide can be harmful to a baby developing in the womb and cause severe abnormalities. So, you must not become pregnant or get someone pregnant while taking this drug and for a time afterwards. Women must not become pregnant for at least 4 weeks after the end of treatment. Men should not get someone pregnant for at least a week after treatment.
Your doctor will talk to you about effective methods of contraception before you have the treatment. They will make sure that you understand the risks of taking lenalidomide and agree to use contraception.
Tell your doctor or specialist nurse straight away if you or your partner become pregnant while having treatment.
It is not known whether this drug comes through into the breast milk. Doctors usually advise that you don’t breastfeed during this treatment.
If you are having tests or treatment for anything else, always mention your cancer treatment. For example, if you are visiting your dentist.
Don’t have immunisations with live vaccines while you’re having treatment and for up to 12 months afterwards. The length of time depends on the treatment you are having.
Ask your doctor or pharmacist how long you should avoid live vaccinations.
In the UK, live vaccines include rubella, mumps, measles, BCG, and yellow fever.
You can usually have:
other vaccines, but they might not give you as much protection as usual
the flu vaccine (as an injection)
the coronavirus (COVID-19) vaccine
Talk to your doctor or pharmacist about the best time to have a vaccine in relation to your cancer treatment.
You can be in contact with other people who have had live vaccines as injections. If someone has had a live vaccine by mouth or nasal spray there may be a small risk the vaccine virus can be passed onto you if your is weakened.
Your healthcare team will let you know if you need to take any precautions if you are in close contact with someone who has had a live vaccine.
For further information about this treatment and possible side effects go to the electronic Medicines Compendium (eMC) website. You can find the patient information leaflet on this website.
You can report any side effect you have to the Medicines and Healthcare products Regulatory Agency (MHRA) as part of their Yellow Card Scheme.
Last reviewed: 13 Oct 2025
Next review due: 13 Oct 2028
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Myelodysplastic syndromes are a group of blood cancers. They are also called myelodysplasia or MDS for short.
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