Thalidomide is used to treat people with myeloma, a type of cancer that affects the plasma cells inside bone marrow. Research is being conducted to determine whether it could be effective in treating other types of cancer.
WHAT IS THALIDOMIDE?
Thalidomide was originally developed to prevent morning sickness during pregnancy. This use was discontinued when it was found to cause birth defects. These birth defects happen because thalidomide changes the growth and development of new blood vessels.
Thalidomide is now used to treat cancer. The drug is primarily used to fight against myeloma. It is safe for adults and should only be avoided during pregnancy.
HOW DOES THALIDOMIDE WORK?
The way thalidomide works in treating cancer is not entirely understood. To grow, cancers need to produce a network of new blood vessels. If these blood vessels do not form, the cancer cannot grow beyond the size of the head of a pin.
Researchers have shown that thalidomide can stop the development of new blood vessels in cancer. Drugs that interfere with the growth of blood vessels this way are called angiogenesis inhibitors or anti-angiogenics.
WHEN IS THALIDOMIDE USED?
Thalidomide is given alongside the chemotherapy drugs melphalan and prednisolone for people 65 or older who have untreated myeloma and whose cancer isn't suitable for high-dose treatment with stem cell support. You may hear this combination referred to as MPT.
Thalidomide is sometimes given in combination with other chemotherapy drugs, as in the CTD regimen (cyclophosphamide, thalidomide, and dexamethasone).
WHAT DOES THALIDOMIDE LOOK LIKE?
Thalidomide is available in 50-mg capsules.
HOW IS CHEMOTHERAPY ADMINISTERED?
Thalidomide capsules should be swallowed whole and taken along with a large glass of water one hour after a meal, preferably at night. It is sometimes given in combination with other chemotherapy medications.
PREVENTING PREGNANCY WHILE TAKING THALIDOMIDE
You should not get pregnant or conceive while taking thalidomide, as it can cause severe abnormalities in developing babies.
Women of childbearing age will have a pregnancy test to confirm that they are not pregnant. This normally happens in the first three days after starting to take thalidomide and is given again every four weeks until four weeks after the treatment has concluded.
Women of childbearing age should use a highly effective contraceptive, such as an implant or injection or the progesterone-only pill. It is not recommended to take the combined oral contraceptive pill, as this increases the risk of developing blood clots, and the likelihood of having a blood clot is already increased when you take thalidomide. Women should use contraception for four weeks before starting treatment, then throughout the duration of the treatment and the four weeks after it has concluded.
Men who are taking thalidomide should use a condom while having sex with women of childbearing age or if the woman is pregnant. They should continue to wear a condom while having sex for the entire treatment with thalidomide and for one week after they have completed their treatment.
Due to the thalidomide's potential for causing birth defects, it is likely you will have to participate in a birth-control program. Your doctor or specialist nurse will give you information in writing about the risks posed by thalidomide and the best ways to keep from getting pregnant.
Women of childbearing age can only be given four weeks of thalidomide treatment at a time. This is to allow for a pregnancy test to be taken with each new cycle. Thalidomide can only be prescribed by a hospital pharmacist, so you will have to visit the hospital frequently. Other patients may be prescribed up to 12 weeks of thalidomide at a time.
POSSIBLE SIDE EFFECTS OF THALIDOMIDE
Each person's reaction to cancer treatment is different: while some people develop very few side effects, others may experience more. The side effects described below will not affect everyone who is treated with the drug. We have outlined only the most common.
If you notice you develop any side effects that are not listed here, talk to your doctor or specialist nurse.
RISK OF BLOOD CLOTS
Cancer can increase the risk of blood clots (thrombosis), and thalidomide may pose an additional risk. You can take medication to think out your blood, which will help keep blood clots from forming.
A blood clot may cause symptoms such as pain, reddening or swelling in a leg, difficulty breathing, and pain in the chest. Some blood clots can be very severe, so it is important to tell your doctor immediately if you have any of these symptoms.
TEMPORARILY REDUCED NUMBER OF BLOOD CELLS
In itself, thalidomide only has a slight effect on the number of blood cells you have. However, if it is given with chemotherapy, the number of cells in your blood may fall to low levels. You will have regular tests done to count your number of blood cells.
TIREDNESS AND DROWSINESS
It is not uncommon for people to feel drowsy or sleepy when taking thalidomide. Tell your doctor if this is a problem. Taking the pills at night can help. You may find that your drowsiness gets better as you continue to take the drug. It is important not to operate heavy machinery or drive if you are feeling drowsy.
In general, it may help to drink lots of fluids, eat more fiber, and get some light exercise. You may need to take drugs (laxatives) to help. Your doctor can prescribe these or you can buy them at the pharmacy.
NUMBNESS OR TINGLING IN THE HANDS AND FEET
This is caused by the effect of thalidomide on the nerve endings, and is known as peripheral neuropathy. You may also notice that you have difficulty performing such tasks as buttoning your clothing. If you notice you have any of these side effects, tell your doctor immediately. Usually, your doctor will either tell you to stop taking thalidomide or lower the dose. This is necessary so that the symptoms don't get worse. These symptoms can be permanent or can get better over time.
Some people find that thalidomide gives them headaches. If this happens, tell your doctor or nurse. They can give you painkillers to help.
DIZZINESS WHEN STANDING UP
You may feel light-headed for a few moments if you stand up quickly. This is caused by a temporary decrease in your blood pressure. It may help to make slow movements when getting up. Also, it is sometimes helpful to go from lying down to sitting up and then stand up. Tell your doctor if you have ever had problems with blood pressure and also tell them the medication you are taking.
Thalidomide can cause skin rash, dryness, and itchiness. Your doctor can prescribe medicines to help with this. From time to time, thalidomide can cause a more serious rash with blisters to develop. Tell your doctor immediately if this happens.
SWELLING IN THE ANKLES
You may find that your ankles become swollen, especially if you have been standing or sitting for a while. Putting your feet up while sitting can help with this problem. Talk to your doctor about the drugs that can help with this. If the swelling causes you discomfort, your doctor may prescribe means of support to keep this under control.
NAUSEA AND VOMITING
This is normally mild. Your doctor can prescribe antiemetic drugs to prevent or greatly reduce your nausea and vomiting.
If your nausea remains uncontrolled or continues, tell your doctor, as they can prescribe other drugs that could work better. Some drugs can cause constipation. Tell your doctor or nurse if this is a problem.
LOSS OF APPETITE
Some people lose their appetite while taking thalidomide. This can be mild and last for a few days. If it doesn't get better, request to see a dietitian or specialist nurse at your hospital. They can give you advice on how to improve your appetite and maintain a healthy weight.
ADDITIONAL INFORMATION ON THALIDOMIDE
Thalidomide may affect your ability to drive. Do not drive if you feel dizzy, have blurry vision, or feel excessively tired or drowsy.
Some drugs, including those bought over the counter in a store or pharmacy, may be harmful to you while you are undergoing cancer treatment. Tell your doctor if you are taking any medication, including over-the-counter drugs, complementary therapies, and herbal remedies.
There is a potential risk that thalidomide may be present in breast milk, and therefore women are recommended not to breast feed during the treatment and for a few months afterward.
If you are admitted to the hospital for any reason not related to cancer, it is important that you tell your doctors and nurses caring for you that you are being treated with thalidomide.
OTHER ISSUES TO KEEP IN MIND ABOUT THALIDOMIDE CAPSULES
It is important to take the pills as indicated by your doctor, nurse, or pharmacist.
Keep the capsules in their original packaging.
Keep them in a safe place out of the reach of children. Pregnant women should not handle the capsules.
Thalidomide can interact with alcohol. It is advisable to refrain from drinking alcohol while taking thalidomide.
If you forget to take a capsule, do not take a double dose. Tell your doctor and maintain your normal dose schedule.
If you vomit right after taking the capsules, get in touch with your doctor.
When planning trips abroad, check to see whether the country you are visiting has any special rules about thalidomide. In Australia, for example, people must provide a doctor's letter stating why the patient is taking the drug.
If your doctor decides to halt your treatment, return the remaining capsules to the hospital. Do not flush them down the toilet or throw them away.