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Alemtuzumab (Campath)

Generic name: Alemtuzumab (Campath) [ ay-lem-TU-zoo-mab ]
Drug class: CD52 monoclonal antibodies

Medically reviewed by Last updated on Sep 18, 2023.


  • Severe and sometimes life-threatening infusion reactions have happened. You will be closely watched during the infusion and for some time after. Severe infusion reactions may also happen up to 48 hours or longer after the infusion. Tell your doctor right away if you have chest pain; passing out; fast or slow heartbeat, or abnormal heartbeat; fever; hives; itching; rash; severe headache or dizziness; shortness of breath, wheezing, or other trouble breathing; swelling of the mouth, face, lips, throat, or tongue; tightness in the chest or throat; abnormal hoarseness; or coughing up blood.
  • Other infusion reactions include change in taste, chills, dizziness, flushing, upset stomach, pain, feeling tired, or not able to sleep. Talk with the doctor.
  • This medicine may cause very bad and sometimes deadly autoimmune problems like some blood problems. Side effects may happen while you get alemtuzumab (campath) and for 4 years after you stop treatment. You will need to have your blood work and urine checked while getting alemtuzumab (campath) and after getting it as you have been told by your doctor. Talk with your doctor.
  • Very bad and sometimes deadly infections have happened in patients who take alemtuzumab (campath). If you have any infection, are taking antibiotics now or in the recent past, or have had many infections, talk with your doctor.
  • Rarely, strokes and tears in blood vessels in the head and neck have happened with alemtuzumab when used for MS (multiple sclerosis). Most of the time, this happened within 1 day after getting alemtuzumab (campath) but can happen a few days after treatment. These health problems can lead to long-term disability and can be deadly. Closely read the part in this leaflet which lists when to call your doctor.

Uses of Alemtuzumab:

  • It is used to treat a type of leukemia.
  • It may be given to you for other reasons. Talk with the doctor.

What do I need to tell my doctor BEFORE I take Alemtuzumab?

  • If you are allergic to alemtuzumab (campath); any part of alemtuzumab (campath); or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
  • If you have an infection.
  • If you have a weak immune system or a disease that may cause a weak immune system like HIV.
  • If you have ever had any of these health problems: Any type of cancer or PML.
  • If you are breast-feeding. You may need to avoid breast-feeding for some time after getting alemtuzumab (campath).

This is not a list of all drugs or health problems that interact with alemtuzumab (campath).

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take alemtuzumab (campath) with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take Alemtuzumab?

  • Tell all of your health care providers that you take alemtuzumab (campath). This includes your doctors, nurses, pharmacists, and dentists.
  • You may have more chance of getting an infection. Wash hands often. Stay away from people with infections, colds, or flu.
  • Call your doctor right away if you have any signs of infection like fever, chills, flu-like signs, very bad sore throat, ear or sinus pain, cough, more sputum or change in color of sputum, pain with passing urine, mouth sores, or a wound that will not heal.
  • You may bleed more easily. Be careful and avoid injury. Use a soft toothbrush and an electric razor.
  • Call your doctor right away if you have any signs of bleeding problems, like bruising; black, tarry, or bloody stools; bleeding gums; blood in the urine; coughing up blood; cuts that take a long time to stop bleeding; feel dizzy; feeling very tired or weak; nosebleeds; pain or swelling; throwing up blood or throw up that looks like coffee grounds; or very bad headache.
  • Gallbladder problems have happened with alemtuzumab (campath). Sometimes, these problems can be life-threatening. Talk with the doctor.
  • A very bad brain problem called progressive multifocal leukoencephalopathy (PML) may happen with alemtuzumab (campath). It may cause disability or can be deadly. Tell your doctor right away if you have signs like confusion, memory problems, low mood (depression), change in the way you act, change in strength on 1 side is greater than the other, trouble speaking or thinking, change in balance, or change in eyesight.
  • This medicine may affect fertility. Fertility problems may lead to not being able to get pregnant or father a child.
  • This medicine may cause harm to an unborn baby. A pregnancy test will be done before you start alemtuzumab (campath) to show that you are NOT pregnant.
  • Women must use birth control while taking alemtuzumab (campath) and for some time after the last dose. Ask your doctor how long to use birth control. If you get pregnant, call your doctor right away.
  • If you used alemtuzumab (campath) when you were pregnant, tell your baby's doctor.

How is this medicine (Alemtuzumab) best taken?

Use alemtuzumab (campath) as ordered by your doctor. Read all information given to you. Follow all instructions closely.

  • It is given as an infusion into a vein over a period of time.
  • Other drugs may be given to help with infusion side effects.
  • Drink lots of noncaffeine liquids every day unless told to drink less liquid by your doctor.
  • Talk with your doctor before getting any vaccines. Use of some vaccines with alemtuzumab (campath) may either raise the chance of an infection or make the vaccine not work as well.

What do I do if I miss a dose?

  • Call your doctor to find out what to do.

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Signs of gallbladder problems like pain in the upper right belly area, right shoulder area, or between the shoulder blades; yellow skin or eyes; fever with chills; bloating; or very upset stomach or throwing up.
  • Signs of high or low blood pressure like very bad headache or dizziness, passing out, or change in eyesight.
  • Weakness on 1 side of the body, trouble speaking or thinking, change in balance, drooping on one side of the face, or blurred eyesight.
  • Feeling confused.
  • Trouble walking.
  • Neck pain.
  • Chest pain or pressure.
  • A burning, numbness, or tingling feeling that is not normal.
  • Shortness of breath.
  • Feeling very tired or weak.
  • Redness or white patches in mouth or throat.
  • Swollen gland.
  • Fast, slow, or abnormal heartbeat.
  • Sweating that is not normal.
  • Patients with cancer who take alemtuzumab (campath) may be at a greater risk of getting a severe health problem called tumor lysis syndrome (TLS).This may lead to death. Call your doctor right away if you have a fast or abnormal heartbeat; any passing out; trouble passing urine; muscle weakness or cramps; upset stomach, throwing up, diarrhea, or not able to eat; or feel sluggish.

What are some other side effects of Alemtuzumab?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

  • Anxiety.
  • Headache.
  • Upset stomach or throwing up.
  • Stomach pain or diarrhea.
  • Trouble sleeping.
  • Not hungry.
  • Back pain.
  • Muscle pain.
  • Feeling tired or weak.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at

If OVERDOSE is suspected:

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

How do I store and/or throw out Alemtuzumab?

  • If you need to store alemtuzumab (campath) at home, talk with your doctor, nurse, or pharmacist about how to store it.

Consumer Information Use and Disclaimer

  • If your symptoms or health problems do not get better or if they become worse, call your doctor.
  • Do not share your drugs with others and do not take anyone else's drugs.
  • Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
  • Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.
  • Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about alemtuzumab (campath), please talk with your doctor, nurse, pharmacist, or other health care provider.
  • If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Frequently asked questions

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.