Lenalidomide belongs to the class of cancer-fighting medications called antineoplastics, and specifically to the group of antineoplastics known as immunomodulatory agents. It has several actions that reduce the growth of cancer cells and increase the activity of the body's defense system against the cancer cells.

Lenalidomide is used, in combination with dexamethasone, to treat multiple myeloma (a type of cancer of the bone marrow) for people who are not eligible for a stem cell transplant. It is also used to treat anemia for people with rare bone marrow disorders (myelodysplastic syndromes).

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

The recommended starting dose of lenalidomide for treating multiple myeloma is 25 mg daily, taken by mouth. It is generally taken for 21 days, stopped for 7 days, and then restarted for 21 days. The dosage will be adjusted by your doctor, based on side effects and the effectiveness of the medication.

For myelodysplastic syndromes, the recommended starting dose is 10 mg daily for 21 days, stopped for 7 days and then restarted for 21 days. The dosage will be adjusted by your doctor, based on side effects and the effectiveness of the medication.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

Lenalidomide capsules should be taken at the same time each day and swallowed whole with a glass of water. This medication may be taken with or without food. The capsules should not be broken, chewed, or opened.

It is important to take this medication exactly as prescribed by your doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If more than 12 hours have passed, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication at room temperature, protect it from light and moisture, and keep it out of the reach of children.

2.5 mg
Each opaque capsule, white on one end and blue/green on the other, printed with "REV" and "2.5 mg" in black ink, contains 2.5 mg of lenalidomide. Nonmedicinal ingredients: lactose anhydrous, microcrystalline cellulose, croscarmellose sodium, magnesium stearate, gelatin, titanium dioxide, FD&C Blue No. 2, and yellow iron oxide.

5 mg
Each white opaque capsule printed with "REV" and "5 mg" in black ink contains 5 mg of lenalidomide. Nonmedicinal ingredients: lactose anhydrous, microcrystalline cellulose, croscarmellose sodium, magnesium stearate, gelatin, and titanium dioxide.

10 mg
Each opaque capsule, blue/green on one end and pale yellow on the other end, printed with "REV" and "10 mg" in black ink, contains 10 mg of lenalidomide. Nonmedicinal ingredients: lactose anhydrous, microcrystalline cellulose, croscarmellose sodium, magnesium stearate, gelatin, titanium dioxide, FD&C Blue No. 2, and yellow iron oxide.

15 mg
Each opaque capsule, powder blue on one end and white on the other end, printed with "REV" and "15 mg" in black ink, contains 15 mg of lenalidomide. Nonmedicinal ingredients: lactose anhydrous, microcrystalline cellulose, croscarmellose sodium, magnesium stearate, gelatin, titanium dioxide, and FD&C Blue No. 2.

20 mg
Each opaque capsule, blue/green on one end and powder blue on the other end, printed with "REV" and "20 mg" in black ink, contains 20 mg of lenalidomide. Nonmedicinal ingredients: lactose anhydrous, microcrystalline cellulose, croscarmellose sodium, magnesium stearate, gelatin, titanium dioxide, FD&C Blue No. 2, and yellow iron oxide.

25 mg
Each white opaque capsule printed with "REV" and "25 mg" in black ink contains 25 mg of lenalidomide. Nonmedicinal ingredients: lactose anhydrous, microcrystalline cellulose, croscarmellose sodium, magnesium stearate, gelatin, and titanium dioxide.

Do not take lenalidomide if you:

• are allergic to lenalidomide or any ingredients of the medication
• are allergic to thalidomide or pomalidomide
• are breast-feeding
• are or may become pregnant
• are male and not able to follow the necessary birth control requirements
• have low platelet levels or bleeding disorders

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• back pain
• blood pressure changes
• bone pain
• change in sense of taste
• constipation
• decreased interest in sexual activity
• decreased sense of touch
• diarrhea
• difficulty sleeping
• dizziness
• dry eyes
• dry mouth
• dry skin
• eye pain
• fatigue
• gas
• hair loss
• headache
• hearing problems
• heartburn
• hiccups
• hot flashes
• increased sweating
• irritability
• itchy, red eyes
• itchiness or rash
• joint or muscle pain
• loss of appetite
• mood changes
• mouth inflammation
• muscle weakness
• nausea
• night sweats
• toothache
• tremor
• vomiting
• weight changes

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• abdominal pain
• balance or coordination problems
• chest pain
• confusion
• fainting
• fast or pounding heartbeat
• fever or signs of infection (such as redness or swelling, sore throat, or coughing up mucus)
• increased hair growth
• mouth pain
• mouth sores
• muscle weakness
• numbness or abnormal sensations
• persistent cough (cough that doesn't seem to go away)
• persistent diarrhea (diarrhea that doesn't seem to go away)
• signs of clotting problems (e.g., unusual nosebleeds, bruising, blood in urine, coughing blood, bleeding gums, cuts that don't stop bleeding)
• signs of dehydration (dry mouth, excessive thirst, dark urine)
• signs of depression (e.g., changes in sleep habits, feeling sad, feelings of guilt or worthlessness, losing interest in things you used to enjoy, thoughts of suicide, weight changes)
• signs of high blood sugar (e.g., frequent urination, increased thirst, excessive eating, unexplained weight loss, poor wound healing, infections, fruity breath odour)
• signs of unusual infections (symptoms may include fever or chills, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness)
• signs of kidney problems (e.g., decreased urine production, swelling, fatigue, abdominal pain)
• signs of high blood pressure (e.g., headache)
• signs of low blood pressure such as dizziness, lightheadedness, or fainting
• signs of skin cancer (e.g., unusual growths, sores that don't heal, moles, or skin discolouration)
• skin rash
• swelling of feet or legs
• symptoms of anemia (such as tiredness, weakness, pale skin, or fast or irregular heartbeat)
• signs of sodium or potassium levels being too high or too low (e.g., muscle pain or cramps, weakness, irregular heartbeat)
• symptoms of a chest/lung infection (e.g., shortness of breath, cough, chest pain)
• symptoms of hypothyroidism (e.g., dry skin, constipation, weight gain, fatigue, aches, pains and stiffness, intolerance to cold, depression, memory problems)
• symptoms of liver problems (e.g., abdominal pain, dark urine, itchy skin, loss of appetite, pale stools, yellow eyes or skin)
• symptoms of over active thyroid (e.g., anxiety or nervousness, weight loss, frequent and loose bowel movements, breathlessness, feeling hot, feelings of having rapid, fluttering or pounding heart)
• tingling or numbness in the hands and feet or muscle weakness that interferes with daily activities
• trouble moving arms or legs
• vision changes (e.g., blurred vision)

Stop taking the medication and seek immediate medical attention if any of the following occur:

• abnormal or irregular heartbeat
• flu-like symptoms (e.g., chills, fever, muscle aches, sweating, tiredness)
• signs of blood clot formation (e.g., coughing blood; pains in chest, groin, or leg, especially in calf of leg; weakness or numbness in arm or leg)
• signs of heart problems (e.g., decreased ability to exercise, increased heart rate, shortness of breath, swollen ankles, tightness in the chest)
• signs of organ transplant rejection (e.g., flu-like symptoms, pain at transplant area, weight gain)
• signs of muscle damage (e.g., unexplained muscle pain, tenderness or weakness, or brown or discoloured urine)
• signs of stroke (e.g., sudden and unexplained shortness of breath, sudden loss of coordination, sudden or severe headache, sudden slurring of speech, sudden vision changes)
• symptoms of graft vs. host disease (GVHD; itchy, painful rash, diarrhea, abdominal pain, liver problems)
• symptoms of a serious allergic reaction (such as difficulty breathing, hives, or swelling of the face or throat)
• symptoms of bleeding (including vomiting blood or material that looks like coffee grounds, dark or bloody stools, or blood in the urine)
• symptoms of progressive multifocal leukoencephalopathy (e.g., seizures, vision loss, trouble thinking clearly, difficulty speaking, difficulty walking)
• symptoms of lung problems (such as coughing, shortness of breath, or wheezing)
• symptoms of serious skin reactions (e.g., a skin rash that spreads quickly or covers a large area of the body; blisters, especially around the eyes, nose, and mouth; shedding of the skin; unexplained skin pain over a large body area)
• symptoms of tumour lysis syndrome (e.g., producing less urine, cloudy urine, kidney problems, muscle spasms, nausea, shortness of breath)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Before you begin taking a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should take this medication.

Bleeding: Lenalidomide may cause a reduced number of platelets in the blood, which can make it difficult to stop cuts from bleeding. If you notice any signs of bleeding, such as frequent nosebleeds, unexplained bruising, or black and tarry stools, notify your doctor as soon as possible. Your doctor will order routine blood tests to make sure potential problems are caught early.

Blood clots: Lenalidomide increases the risk of developing blood clots in the legs and lungs. If you experience sudden shortness of breath, blurred vision, difficulty speaking, chest pain, arm or leg pain, and swelling, contact your doctor immediately.

Blood donation: Do not give blood during and for 4 weeks after your treatment with lenalidomide. If a pregnant woman received your donated blood, her baby could be exposed to lenalidomide and might be born with birth defects.

Cardiovascular effects: This medication may have effects on the heart and circulatory (blood vessels) system, including irregular heartbeat, heart attack, stroke, and changes in blood pressure. If you have heart disease, high blood pressure, and other diseases of the heart and blood system, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Diabetes: Lenalidomide may cause an increase in blood sugar levels and glucose tolerance may change. People with diabetes may find it necessary to monitor their blood sugar more frequently while using this medication.

If you have diabetes or are at risk for developing diabetes, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Drowsiness/reduced alertness: This medication is not expected to make you drowsy or impair your ability to drive or use machinery. However, it may make some people feel weak. Do not drive or use machinery if you feel weak.

Graft versus host disease: Lenalidomide has been reported to cause graft versus host disease, a complication from stem cell transplants that occurs when the immune system reacts to the transplanted cells. Organ rejection may also occur when lenalidomide is used after a solid organ transplant. If you have had a transplant, talk to your doctor about symptoms of rejection that you need to be aware of.

Hypersensitivity reaction: Several severe allergic reactions have been reported by people taking lenalidomide. These rare reactions may start with a skin reaction, such as a severe rash. These reactions can affect organ function and should be treated as an emergency. Get immediate medical attention if you have symptoms of a severe allergic reaction, including fever, swollen glands, yellowing of the skin or eyes, or flu-like symptoms with skin rash or blistering.

Infections: When lenalidomide decreases the number of cells that fight infection in the body (white blood cells), it increases the risk of infections. It may also cause infections such as herpes zoster or hepatitis B to flare up. If you notice any signs of an infection, such as fever or chills, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness, contact your doctor immediately.

Kidney function: Kidney disease or reduced kidney function may cause this medication to build up in the body, causing side effects. If you have kidney problems, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Lactose intolerance: This medication contains lactose. If you have galactose intolerance (galactosemia, glucose-galactose malabsorption, or Lapp lactase deficiency) you should not take this medication. Talk to your doctor about other alternatives.

Liver function: This medication has been reported to cause a decrease in liver function including fatal liver failure. If you experience symptoms of liver problems such as fatigue, feeling unwell, loss of appetite, nausea, yellowing of the skin or whites of the eyes, dark urine, pale stools, abdominal pain or swelling, and itchy skin, contact your doctor immediately. Your doctor may want to test your liver function regularly with blood tests while you are taking this medication.

Progressive multifocal leukoencephalopathy (PML): There have been reports of PML after using lenalidomide. PML is a rare disorder that causes nerve damage in the brain. If you experience memory loss, vision changes, trouble thinking, personality changes or difficulty walking, contact your doctor immediately.

Second cancers: A small number of patients with multiple myeloma have reported second cancers such as skin cancers or other invasive cancers. Talk to your health care provider if you have any concerns.

Thyroid problems: Both hypothyroidism (low thyroid) and hyperthyroidism (overactive thyroid) have been reported with lenalidomide. If you have thyroid problems, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Tumour lysis syndrome: Lenalidomide, like many other cancer medications, causes many cancer cells to be suddenly killed when treatment is first started. This can overwhelm the body with waste products from the cells. As a result, the body may not be able to keep up with getting rid of all the waste. When this happens, you may experience nausea, shortness of breath, or notice cloudy urine or joint pain. This is called tumour lysis syndrome. Your doctor may prescribe some medications to help your body get rid of the waste products. Make sure you understand how to use these medications and report any of these signs or symptoms to your doctor immediately.

Pregnancy: This medication must not be used during pregnancy because of the potential for it to cause serious birth defects. Women who take lenalidomide must use 2 methods of birth control for 4 weeks before starting treatment with lenalidomide, during treatment with lenalidomide, and for at least 4 weeks after treatment has stopped.

Your doctor will ask you to do 2 pregnancy tests before starting lenalidomide and regularly during treatment with lenalidomide. If you become pregnant while taking lenalidomide, contact your doctor immediately.

Men who take lenalidomide must use a latex condom during sexual encounters with women who can become pregnant. They must continue to use a condom for at least 4 weeks after treatment has stopped.

Breast-feeding: The safety of taking lenalidomide while breast-feeding has not been determined. It is not known if lenalidomide passes into breast milk. Because a baby may be seriously harmed if exposed to this medication, breast-feeding mothers should not use this medication.

Children: The safety and effectiveness of using this medication have not been established for children.

Seniors: People over the age of 65 who take lenalidomide may be at increased risk of developing side effects associated with the heart and kidneys. Your doctor may want to monitor you more closely while you are taking this medication.

There may be an interaction between lenalidomide and any of the following:

• abatacept
• anakinra
• bacillus Calmette-Guérin (BCG)
• baricitinib
• bisphosphonates (e.g., alendronate, risedronate)
• canakinumab
• certolizumab pegol
• cladribine
• clozapine
• darbepoetin
• deferiprone
• denosumab
• dexamethasone
• digoxin
• echinacea
• epoetin alfa
• estrogens and progestins (such as those found in birth control pills and hormone replacement therapies)
• fingolimod
• leflunomide
• mesalamine
• natalizumab
• nivolumab
• ocrelizumab
• ofatumumab
• olsalazine
• ozanimod
• pembrolizumab
• pimecrolimus
• roflumilast
• siponimod
• sulfasalazine
• tacrolimus
• tocilizumab
• tofacitinib
• trastuzumab
• upadacitinib
• vaccines
• vedolizumab

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.