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Alemtuzumab Injection (Chronic Lymphocytic Leukemia)

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


Alemtuzumab injection (Campath) is only available though a special restricted distribution program (Campath Distribution Program). In order to receive alemtuzumab injection (Campath) your doctor must be registered with the program, and follow the requirements. The Campath Distribution Program will ship the medication directly to the doctor, hospital, or pharmacy.


Alemtuzumab injection may cause a decrease in the number of blood cells made by your bone marrow. If you experience any of the following symptoms, call your doctor immediately: unusual bruising or bleeding, small reddish or purple blood spots on your body, pale skin, weakness, or excessive tiredness. You will need to take extra precautions to avoid injury during your treatment because you may bleed heavily from minor cuts or scrapes. Brush your teeth with a soft toothbrush, use an electric razor if you shave, and avoid contact sports and other activities that may cause injury.

Alemtuzumab injection may decrease your ability to fight infection and increase the risk that you will get a serious or life threatening infection. Call your doctor immediately if you develop any signs of infection such as fever, cough, sore throat, or a wound that is red, oozing pus, or slow to heal.

You will need to take precautions to decrease the risk of infection during your treatment with alemtuzumab injection. Your doctor will prescribe certain medications to prevent infection. You will take these medications during your treatment and for at least 2 months after your treatment. Take these medications exactly as directed. You should also wash your hands often and avoid people who have contagious infections such as coughs and colds. If you need any type of blood transfusion during your treatment with alemtuzumab injection, you should receive only irradiated blood products (blood products that have been treated to prevent a certain serious reaction that may occur in people who have weakened immune systems).

You may experience a serious or fatal reaction while you receive a dose of alemtuzumab injection. You will receive each dose of medication in a medical facility, and your doctor will monitor you carefully while you are receiving the medication. Your doctor will prescribe certain medications to prevent these reactions. You will take these medications shortly before you receive each dose of alemtuzumab. Your doctor will start you on a low dose of alemtuzumab and gradually increase your dose to allow your body to adjust to the medication. If you experience any of the following symptoms during or after your infusion, tell your doctor immediately: fever; chills; nausea; vomiting; hives; rash; itching; difficulty breathing or swallowing; slowed breathing; tightening of the throat; swelling of the eyes, face, mouth, lips, tongue or throat; hoarseness; dizziness; lightheadedness; fainting; fast or irregular heartbeat; or chest pain.

Keep all appointments with your doctor and the laboratory. Your doctor will order certain tests during and after your treatment to check your body's response to alemtuzumab injection.

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

Why is this medication prescribed?

Alemtuzumab injection is used to treat B-cell chronic lymphocytic leukemia (B-CLL; a slowly developing cancer in which too many of a certain type of white blood cell accumulate in the body). Alemtuzumab is in a class of medications called monoclonal antibodies. It works by activating the immune system to destroy cancer cells.

Alemtuzumab is also available as an injection (Lemtrada) that is used to treat multiple sclerosis (a disease in which the nerves do not function properly; you may experience weakness, numbness, loss of muscle coordination and problems with vision, speech, and bladder control). This monograph only gives information about alemtuzumab injection (Campath) for B-CLL. If you are receiving alemtuzumab for multiple sclerosis, read the monograph entitled Alemtuzumab Injection (Multiple Sclerosis).

How should this medicine be used?

Alemtuzumab injection comes as a solution (liquid) to be injected intravenously (into a vein) over at least 2 hours by a doctor or nurse in a hospital or medical office. At first, alemtuzumab injection is usually given in gradually increasing doses for 3 to 7 days to allow the body to adjust to the medication. Once the body has adjusted to the needed dose of alemtuzumab injection, the medication is usually given 3 times weekly on alternate days (usually Monday, Wednesday, and Friday) for up to 12 weeks.

The medications you receive before each dose of alemtuzumab injection might make you sleepy. You will probably want to ask a family member or friend to come with you when you receive your medication and to take you home afterward.

Although your condition may improve as soon as 4 to 6 weeks after you begin treatment with alemtuzumab injection, your treatment will probably last for 12 weeks. Your doctor will decide whether to continue your treatment and may adjust your dose depending on how well the medication works for you and on the side effects you experience.

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 injection or any other medications.
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take while receiving alemtuzumab injection.
  • tell your doctor if you have or have ever had any medical conditions.
  • tell your doctor if you or your partner are pregnant or plan to become pregnant. You will have to take a pregnancy test before starting treatment and use birth control to prevent pregnancy during your treatment and for 3 months after your final dose. If you become pregnant during your treatment with alemtuzumab injection, call your doctor immediately. Alemtuzumab may harm the fetus.
  • tell your doctor if you are breastfeeding. Do not breastfeed during treatment with alemtuzumab and for 3 months after the final dose.
  • do not have any live vaccinations during or shortly after your treatment with alemtuzumab injection without talking to your doctor. Women receiving alemtuzumab injection while pregnant should talk to their pediatrician as their infant may not be able to receive live vaccines for a certain period of time.
  • you should know that this medication may decrease fertility in men and women. Talk to your doctor about the risks of receiving alemtuzumab.
  • if you are having surgery, including dental surgery, tell the doctor or dentist that you are receiving alemtuzumab injection.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

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:

  • nausea
  • vomiting
  • stomach pain
  • diarrhea
  • loss of appetite
  • mouth sores
  • headache
  • anxiety
  • difficulty falling asleep or staying asleep
  • uncontrollable shaking of a part of the body
  • muscle pain

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:

  • drooping on one side of the face; sudden weakness or numbness of an arm or leg, especially on one side of the body; or difficulty speaking or understanding
  • swelling in legs and ankles, weight gain, fatigue. or foamy urine (may occur months or years after your final dose)

Alemtuzumab 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.

Symptoms of overdose may include the following:

  • tightening of the throat
  • difficulty breathing
  • cough
  • decreased urination
  • unusual bruising or bleeding
  • reddish or purple spots on the skin
  • pale skin
  • weakness
  • excessive tiredness
  • sore throat, fever, chills, and other signs of infection
  • nausea
  • vomiting
  • hives
  • rash
  • itching
  • swelling of the eyes, face, mouth, throat, lips, or tongue
  • fast or irregular heartbeat
  • fainting
  • chest pain

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

  • Campath®
Last Revised - 10/15/2023