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What thalidomide is

Thalidomide is pronounced as tha-lid-oh-mide. It is a type of cancer growth blocker. Researchers are still looking at how thalidomide works. It affects all sorts of cell processes, including how cells divide and grow. We know that it interferes with chemicals that cells use to tell each other to grow.

All cancers need a blood supply, so that they can grow. Thalidomide stops tumours making their own blood vessels. Angiogenesis (pronounced ann-gee-oh-jen-eh-sis) means the growth of new blood vessels. So thalidomide is an angiogenesis inhibitor (an anti angiogenic drug).

Thalidomide is a treatment for myeloma. You may have it on its own or with the chemotherapy drug melphalan, and steroids, such as dexamethasone or prednisone. You can find out more about when doctors prescribe thalidomide in the treating myeloma section.

You may also have thalidomide as part of a clinical trial for other cancers.


How you have thalidomide

You take thalidomide each day as capsules with a glass of water, at night. You usually start on a low dose and your doctor then increases the dose unless you get bad side effects. For myeloma you may take it for up to a year and 5 months.

You can take thalidomide with or without food. It is very important that you take capsules according to the instructions your doctor or pharmacist gave you. You should take the right dose, not more or less. And never stop taking a cancer drug without talking to your specialist first.

If you forget to take thalidomide at your regular time and less than 12 hours have passed take your capsules immediately. If more than 12 hours have passed do not take the capsules. Take your next capsules at the usual time the next day.


Importance of preventing pregnancy

Thalidomide can cause birth defects in children. So you must not become pregnant or father a child if you are taking this drug. Your doctor will talk to you about contraception before you have the treatment.

Some people worry about taking thalidomide but it does not cause physical defects in adults.

Because thalidomide causes birth defects, you have to sign a consent form and register with the company who make thalidomide. You do this before you start treatment. This is to make sure you understand the risks of taking thalidomide and agree to use contraception for a specified period of time.

Your doctor will give you a prescription for thalidomide for 4 weeks if you are a woman of child bearing age. After 4 weeks they give you another prescription. At the start of your treatment and with each new prescription, you need to contact the drug company and answer a confidential telephone questionnaire. Your doctor or nurse will tell you all about this.

If you are a man or a woman of non child bearing age you can have a prescription for up to 3 months. 

Pregnant women should not touch or handle thalidomide. You must store it in a place where pregnant women or children cannot reach it.


Common side effects

More than 10 in every 100 people have one or more of the side effects listed below.

A temporary drop in the number of blood cells made by the bone marrow, causing

  • An increased risk of getting an infection from a drop in white blood cells – it is harder to fight infections and you can become very ill. You may have headaches, aching muscles, a cough, sore throat, pain passing urine or feel cold and shivery
  • Tiredness and breathlessness due to a drop in red blood cells (anaemia) – you may need a blood transfusion
  • Bruising more easily due to a drop in platelets – you may have nosebleeds, bleeding gums after brushing your teeth, or lots of tiny red spots or bruises on your arms or legs (known as petechia)

Some of these side effects can be life threatening, particularly infections. You should contact your doctor or nurse if you have any of these effects. Your doctor will check your blood counts regularly to see how well your bone marrow is working.

Other common side effects include

  • Drowsiness (feeling tired and sleepy) – this affects up to 8 in 10 people taking thalidomide (80%) so it is best to take the drug at bedtime and avoid drinking alcohol while having this treatment
  • Nerve damage can cause numbness or tingling in the fingers and toes and difficulty doing small things, like doing up buttons – this affects more than 1 in 10 people (10%) who take thalidomide. Tell your doctor or nurse if you have it. Your doctor may need to reduce the dose you take
  • Shaky hands (tremor) caused by nerve damage
  • Dizziness occurs in around 2 out of 10 people (20%)
  • Constipation happens in most people – drink at least 2 to 3 litres of fluid a day and eat a diet high in fibre. Your doctor or nurse can give you a laxative if you need one
  • Blood clots occur in around 2 out of 10 people (20%) – if this happens you will have treatment to thin your blood, dissolve any clots and stop any more developing. If you are at higher than normal risk of developing blood clots, your doctor will give you aspirin when you start thalidomide treatment. The aspirin prevents blood clots
  • Loss of fertility – it is not known exactly what effect this drug may have on your ability to have children. Do talk to your doctor before starting treatment if you are thinking of having a baby in the future

Occasional side effects

Between 1 and 10 in every 100 people have one or more of these.

  • Confusion
  • Skin changes – about 2 out of 10 people (20%) have a rash. Your skin may also be dry and itchy
  • Mood changes – you may feel sad and depressed
  • Pain may occur in your bones, muscles, stomach and you may have headaches – mild painkillers usually control it
  • A sore mouth
  • Weakness
  • Changes in your heart muscle which are usually temporary but for a small number of people may be permanent – your doctor will check your heart before and after your treatment
  • Swelling of your legs due to fluid build up (known as peripheral oedema)
  • Feeling sick is usually well controlled with anti sickness medicines
  • Sinusitis (inflammation of the sinuses) – you may have a runny nose and a sore throat. This affects 1 in 20 people (5%) taking thalidomide
  • Indigestion
  • Low blood pressure – you may find that your blood pressure drops when you stand up too quickly and you may feel dizzy
  • Loss of appetite
  • Changes to your blood chemistry – the levels of calcium, sodium and potassium may be lower or higher than normal. You may not have any symptoms from this but you will have regular blood tests to check the levels of these minerals
  • Slow heart beat
  • An increased risk of certain blood disorders (acute myeloid leukaemia and myelodysplastic syndromes) – this affects 2 to 4 out of 100 people (2 – 4%)

Rare side effects

Fewer than 1 in 100 people have these effects.

  • A serious reaction called Stevens Johnson syndrome, which is a painful inflammation of the eyes, eyelids and skin
  • Low levels of thyroid hormones leading to causes weight gain, tiredness and a lack of energy
  • Blockage of the bowel
  • Low sex drive and men may have difficulty getting an erection
  • Liver changes that are very mild and unlikely to cause symptoms – the liver will almost certainly go back to normal when treatment is finished, but you will have regular blood tests to check how well your liver is working
  • High uric acid levels in the blood due to the breakdown of tumour cells (tumour lysis syndrome) – you will have regular blood tests to check your uric acid levels and may have a tablet called allopurinol to take. Drinking plenty of fluids helps to flush out the excess uric acid
  • An allergic reaction – let your nurse know if you have any skin rashes, itching, swelling of the eyes, mouth or face, or difficulty breathing
  • Loss of hearing
  • Seizures (fits)
  • Kidney changes that are mild and unlikely to cause symptoms – they will almost certainly go back to normal when treatment is finished, but you will have regular blood tests to check how well your kidneys are working
  • Worsening of Parkinson’s disease symptoms, such as shaking (tremor) depression or confusion
  • Pain in the upper abdomen or back for a few days, which may be severe – it is caused by inflammation of the pancreas and you may also feel sick, have a high temperature and a faster heart rate

Important points to remember

You may only have a few of the side effects mentioned above. A side effect may get worse through your course of treatment or more side effects may develop as the course goes on. This depends on

  • How many times you've had the drug before
  • Your general health
  • The amount of the drug you have (the dose)
  • Other drugs you are having

Talk to your doctor, pharmacist or nurse about all your side effects so they can help you manage them. They can give you advice or reassure you. Your nurse will give you a contact number to ring if you have any questions or problems. If in doubt, call them.

Breastfeeding is not advisable during this treatment because the drug may come through in the breast milk.

You must not donate blood and men must not donate semen during treatment and for a week afterwards.

Tell your doctor about any other medicines you are taking, including vitamins, herbal supplements and other over the counter remedies – some drugs can react together. Thalidomide can react with

  • Medicines that cause sleepiness and may make you more sleepy
  • Medicines that slow the heart rate or treat heart problems
  • Medicines that thin the blood (anti coagulants)
  • Some other cancer treatments


You should not have immunisations with live vaccines while you are having treatment or for at least 6 months afterwards. In the UK, these include rubella, mumps, measles (usually given together as MMR), BCG, yellow fever and Zostavax (shingles vaccine).

You can have other vaccines, but they may not give you as much protection as usual until your immune system has fully recovered from your treatment. It is safe to have the flu vaccine.

It is safe for you to be in contact with other people who've had live vaccines as injections. There can be problems with vaccines you take by mouth (oral vaccines), but not many people in the UK have these now. So there is usually no problem in being with any baby or child who has recently had any vaccination in the UK. You might need to make sure that you aren't in contact with anyone who has had oral polio, cholera or typhoid vaccination recently, particularly if you live abroad.


More information on thalidomide

This page does not list all the very rare side effects of this treatment that are very unlikely to affect you. For further information look at the Electronic Medicines Compendium website at

If you have a side effect not mentioned here that you think may be due to this treatment you can report it to the Medicines Health and Regulatory Authority (MHRA) at

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Updated: 3 May 2013