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Alemtuzumab Injection (Multiple Sclerosis)

pronounced as (al'' em tooz' oo mab)


Alemtuzumab injection may cause serious or life-threatening autoimmune disorders (conditions in which the immune system attacks healthy parts of the body and causes pain, swelling, and damage), including thrombocytopenia (a low number of platelets [a type of blood cell needed for blood clotting]) and kidney problems. Tell your doctor if you have bleeding problems or kidney disease. If you experience any of the following symptoms, call your doctor immediately: unusual bleeding, swelling of your legs or feet, coughing up blood, bleeding from a cut that is hard to stop, heavy or irregular menstrual bleeding, spots on your skin that are red, pink, or purple, bleeding from gums or nose, blood in urine, chest pain, decrease in urine amount, and fatigue.

You may experience a serious or life-threatening infusion reaction while you receive a dose of alemtuzumab injection or for up to 3 days afterwards. You will receive each dose of medication in a medical facility, and your doctor will monitor you carefully during the infusion and after you receive the medication. It is important that you stay at the infusion center for at least 2 hours after your infusion is completed. If you experience any of the following symptoms during or after your infusion, tell your doctor immediately: fever; chills; nausea; headache; vomiting; hives; rash; itching; flushing; heartburn; dizziness; shortness of breath; difficulty breathing or swallowing; slowed breathing; tightening of throat; swelling of the eyes, face, mouth, lips, tongue or throat; hoarseness; dizziness; lightheadedness; fainting; fast or irregular heartbeat; or chest pain.

Alemtuzumab injection may cause a stroke or tears in your arteries that supply blood to your brain, especially within the first 3 days after treatment. If you experience any of the following symptoms during or after your infusion, tell your doctor immediately: drooping on one side of the face, severe headache, neck pain, sudden weakness or numbness of an arm or leg, especially on one side of the body, or difficulty speaking, or understanding.

Alemtuzumab injection may increase the risk that you will develop certain cancers, including thyroid cancer, melanoma (a type of skin cancer), and certain blood cancers. You should have your skin checked by a doctor for signs of cancer before you begin treatment and yearly thereafter. Call your doctor if you have the following symptoms that may be a sign of thyroid cancer: new lump or swelling in your neck; pain in front of neck; unexplained weight loss; bone or joint pain; lumps or swellings in your skin, neck, head, groin or stomach; changes in mole shape, size, or color or bleeding; small lesion with an irregular border and portions that appear red, white, blue or blue-black; hoarseness or other voice changes that do not go away; difficulty swallowing or breathing; or cough.

Because of the risks with this medication, alemtuzumab injection is available only through a special restricted distribution program. A program called A program called Lemtrada Risk Evaluation and Mitigation Strategy (REMS) Program. Ask your doctor if you have any questions about how you will receive your medication.

Keep all appointments with your doctor and the laboratory. Your doctor will order certain tests to check your body's response to alemtuzumab injection before and during your treatment and for 4 years after you receive your final dose.

Talk to your doctor about the risks of receiving alemtuzumab injection.

Why is this medication prescribed?

Alemtuzumab injection is used to treat adults with various forms of multiple sclerosis (MS; a disease in which the nerves do not function properly and people may experience weakness, numbness, loss of muscle coordination, and problems with vision, speech, and bladder control) who have not improved with at least two or more MS medications including:

  • relapsing-remitting forms (course of disease where symptoms flare up from time to time) or
  • secondary progressive forms (course of disease where relapses occur more often).

Alemtuzumab is in a class of medications called monoclonal antibodies. It works by decreasing the action of immune cells that may cause nerve damage.

Alemtuzumab is also available as an injection (Campath) that is used to treat chronic lymphocytic leukemia (a slowly developing cancer in which too many of a certain type of white blood cell accumulates in the body). This monograph only gives information about alemtuzumab injection (Lemtrada) for multiple sclerosis. If you are receiving alemtuzumab for chronic lymphocytic leukemia, read the monograph entitled Alemtuzumab Injection (Chronic Lymphocytic Leukemia).

How should this medicine be used?

Alemtuzumab injection comes as a solution (liquid) to be injected intravenously (into a vein) over 4 hours by a doctor or nurse in a hospital or medical office. It is usually given once daily for 5 days for the first treatment cycle. A second treatment cycle is usually given once daily for 3 days, 12 months after the first treatment cycle. Your doctor may prescribe an additional treatment cycle for 3 days at least 12 months after the previous treatment.

Alemtuzumab injection helps to control multiple sclerosis, but does not cure it.

Other uses for this medicine

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before receiving alemtuzumab injection,

  • tell your doctor and pharmacist if you are allergic to alemtuzumab, any other medications, or any of the ingredients in alemtuzumab injection. Ask your pharmacist or check the Medication Guide for a list of the ingredients.
  • tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, you are taking or plan to take. Be sure to mention the following: alemtuzumab (Campath; brand name of the product used to treat leukemia); cancer medications; or immunosuppressive medications such as cyclosporine (Gengraf, Neoral, Sandimmune), mycophenolate (Cellcept), prednisone, and tacrolimus (Astagraf, Envarsus, Prograf). Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if you have an infection or human immunodeficiency virus (HIV). Your doctor will probably tell you not to receive alemtuzumab injection.
  • tell your doctor if you have or have ever had tuberculosis (TB; a serious infection that affects the lungs and sometimes other parts of the body), herpes zoster (shingles; a rash that can occur in people who have had chickenpox in the past), genital herpes (a herpes virus infection that causes sores to form around the genitals and rectum from time to time), varicella (chickenpox), liver disease including hepatitis B or hepatitis C, or thyroid, heart, lung, or gallbladder disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you are female, you will need to take a pregnancy test before you start treatment and use birth control during your treatment and for 4 months after your final dose. Talk to your doctor about types of birth control that you can use to prevent pregnancy during this time. If you become pregnant while you are receiving alemtuzumab injection, call your doctor immediately. Alemtuzumab may harm the fetus.
  • check with your doctor to see if you need to receive any vaccinations before receiving alemtuzumab. Tell your doctor if you have received a vaccine within the past 6 weeks. Do not have any vaccinations without talking to your doctor during your treatment.

What special dietary instructions should I follow?

Avoid the following foods that may cause infection at least 1 month before you start receiving alemtuzumab and during your treatment: deli meat, dairy products made with unpasteurized milk, soft cheeses, or undercooked meat, seafood, or poultry.

What side effects can this medication cause?

Alemtuzumab injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • difficulty sleeping or falling asleep
  • pain in legs, arms, toes, and hands
  • back, joint, or neck pain
  • tingling, pricking, chilling, burning, or numb sensation on the skin
  • red, itchy, or scaly skin
  • heartburn
  • swelling of nose and throat

Some side effects can be serious. If you experience any of these symptoms or those listed in the IMPORTANT WARNING section, call your doctor immediately or get emergency medical treatment:

  • shortness of breath, chest pain or tightness, cough, coughing up blood, or wheezing
  • fever, chills, diarrhea, nausea, vomiting, headache, joint or muscle pain, neck stiffness, difficulty walking, or mental status changes
  • bruising or bleeding easily, blood in urine or stool, nose bleeding, bloody vomit, or painful and/or swollen joints
  • excessive sweating, eye swelling, weight loss, nervousness, or fast heartbeat
  • unexplained weight gain, tiredness, feeling cold, or constipation
  • depression
  • thinking about harming or killing oneself or planning or trying to do so
  • genital sores, sensation of pins and needles, or rash on penis or in vaginal area
  • cold sores or fever blisters on or around the mouth
  • painful rash on one side of face or body, with blisters, pain, itching, or tingling in rash area
  • (in women) vaginal odor, white or yellowish vaginal discharge (may be lumpy or look like cottage cheese), or vaginal itching
  • white lesions on tongue or inner cheeks
  • stomach pain or tenderness, fever, nausea, or vomiting
  • nausea, vomiting, stomach pain, extreme tiredness, loss of appetite, yellow eyes or skin, extreme tiredness, dark urine, or bleeding or bruising more easily than normal
  • weakness on one side of the body that worsens over time; clumsiness of the arms or legs; changes in your thinking, memory, walking, balance, speech, eyesight, or strength that last several days; headaches; seizures; confusion; or personality changes
  • fever, swollen glands, rash, seizures, changes in thinking or alertness, or new or worsening unsteadiness or difficulty walking

Alemtuzumab injection may cause other side effects. Call your doctor if you have any unusual problems while receiving this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online ( or by phone (1-800-332-1088).

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

  • headache
  • rash
  • dizziness

What other information should I know?

Ask your pharmacist any questions you have about alemtuzumab injection.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Lemtrada®
Last Revised - 01/15/2021