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Alemtuzumab Side Effects

For the Consumer

Applies to alemtuzumab: intravenous solution

Along with its needed effects, alemtuzumab may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur while taking alemtuzumab:

More common
  • Black, tarry stools
  • blood in the urine
  • chills
  • cough
  • diarrhea
  • dizziness
  • faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  • fast heartbeat
  • fever
  • headache
  • itching, hives, or rash
  • nausea and vomiting
  • painful or difficult urination
  • pale skin
  • sore throat
  • sores, ulcers, or white spots on the lips or in the mouth
  • sweating
  • swollen glands
  • tightness in the chest
  • troubled breathing, exertional
  • unusual bleeding or bruising
  • unusual tiredness or weakness
Less common
  • Bloating or swelling of the face, hands, lower legs, or feet
  • chest pain
  • hoarseness
  • lower back or side pain
  • muscle weakness
  • pounding, or irregular heartbeat or pulse
  • rapid weight gain
  • red or purple spots on the skin, varying in size and remaining after pushing the skin surface
  • Flushing of the face or neck
  • swelling of the eyelids, face, or lips
  • white patches on the tongue, in the mouth, or in folds of the skin, including the genitals
Incidence not known
  • Back pain
  • blindness
  • blurred vision
  • chest discomfort
  • confusion
  • convulsions
  • decreased urine output
  • decreased vision
  • dilated neck veins
  • drowsiness
  • extreme fatigue
  • eye pain
  • feeling of discomfort
  • inability to move the arms and legs
  • inflammation of the joints
  • irregular breathing
  • joint pain, stiffness, or swelling
  • muscle aches or pain
  • numbness, pain, tingling, or weakness
  • painful glands
  • spitting up blood
  • sudden numbness and weakness in the arms and legs
  • swelling of the face, fingers, feet, or lower legs

Some side effects of alemtuzumab may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common
  • Fear or nervousness
  • trouble sleeping
Less common
  • Acid or sour stomach
  • belching
  • bone pain
  • burning, crawling, itching, numbness, prickling, “pins and needles”, or tingling feelings
  • heartburn
  • indigestion
  • lack or loss of strength
  • loss of appetite
  • painful cold sores or blisters on the lips, nose, eyes, or genitals
  • stomach discomfort, upset, or pain
  • swelling or inflammation of the mouth
  • weight loss
  • Bloody nose
  • constipation
  • sensation of temperature change
  • sleepiness
  • stuffy nose
  • tremor
  • unexplained nosebleeds

For Healthcare Professionals

Applies to alemtuzumab: intravenous solution


Median CD4+ lymphocyte counts were 2/mcL 4 weeks after begin of alemtuzumab therapy, 207/mcL two months after discontinuation, and 470/mcL six months after discontinuation. CD8+ cells followed a similar pattern of change. In some patients, CD4+ and CD8+ counts did not return to baseline levels within 1 year after discontinuation.[Ref]

Very common (10% or more): Lymphopenia (97%), neutropenia (77%), anemia (76%), thrombocytopenia (71%), granulocytopenia
Common (1% to 10%): Decrease in CD4 lymphocytes, decrease in CD8 lymphocytes, decrease in T-lymphocyte count, febrile neutropenia, pancytopenia, leukopenia, lymphopenia, purpura
Uncommon (0.1% to 1%): Aplasia bone marrow, disseminated intravascular coagulation, hemolytic anemia, decreased haptoglobin, bone marrow depression, hematology test abnormal[Ref]


Very common (10% or more): Immunogenicity (up to 83%), herpes viral infection (16%), fungal infection (13%), sepsis, cytomegalovirus infection, cytomegalovirus
Common (1% to 10%): Influenza, neutropenic fever
Uncommon (0.1% to 1%): Sepsis, staphylococcal bacteremia, tuberculosis, beta hemolytic streptococcal infections, candidiasis, genital candidiasis, body tinea
Very rare (less than 0.01%): Immune thrombocytopenia
Frequency not reported: Autoimmunity[Ref]

Types of infections reported in the 93 B-CLL patients have included Candida, CMV, Aspergillosis, Mucormycosis, Cryptococcal pneumonia, Listeria monocytogenes meningitis, disseminated Herpes zoster, Herpes simplex, Torulopsis pneumonia, and PCP pneumonia. Infections reported in other trials have included abscess, bacterial infection, Herpes zoster infection, Pneumocystis carinii infection, otitis media, Tuberculosis infection, interstitial pneumonitis, progressive multifocal leukoencephalopathy, and other viral infections.

Postmarketing experiences have included Epstein-Barr virus lymphoproliferative disorder and reactivation of latent viruses.[Ref]


An initial dose of 80 mg caused acute bronchospasm, cough, shortness of breath, followed by anuria and death in one patient. Tumor lysis syndrome may have been a factor.[Ref]

Very common (10% or more): Nasopharyngitis (25%), upper respiratory tract infection (16%), sinusitis (11%), pneumonia
Common (1% to 10%): Cough, dyspnea, bronchitis, chest discomfort, epistaxis, hypoxia, hemoptysis, bronchospasm
Uncommon (0.1% to 1%): Stridor, throat tightness, pulmonary infiltration, pleural effusion, breath sounds decreased, respiratory disorder
Frequency not reported: Respiratory alkalosis[Ref]


Very common (10% or more): Nausea (21%), diarrhea (12%), oropharyngeal pain (11%), abdominal pain (10%), vomiting (10%)
Common (1% to 10%): Dyspepsia, gastrointestinal hemorrhage, ulcerative stomatitis, stomatitis, gastroenteritis, tongue ulceration, gingivitis, hiccup, eructation, dyspepsia, constipation, flatulence, oral candidiasis
Uncommon (0.1% to 1%): Gingival bleeding, dry mouth, paralytic ileus, oral discomfort
Frequency not reported: Duodenal ulcer, intestinal perforation, melena, peptic ulcer, pseudomembranous colitis, colitis, pancreatitis, peritonitis[Ref]

Nervous system

Very common (10% or more): Headache (52%), insomnia (16%), paresthesia (10%), dizziness (10%)
Common (1% to 10%): Dysgeusia, vertigo, tremor, paresthesia, hypoesthesia, hyperkinesia, taste loss
Uncommon (0.1% to 1%): Syncope, abnormal gait, dystonia, hyperesthesia, neuropathy, taste perversion[Ref]


Very common (10% or more): Hypotension, hypertension
Common (1% to 10%): Tachycardia, peripheral edema, vasospasm
Uncommon (0.1% to 1%): Cardiac arrest, myocardial infarction, atrial fibrillation, supraventricular tachycardia, arrhythmia, bradycardia, abnormal ECG, peripheral ischemia, cyanosis, orthostatic hypotension, hot flush
Frequency not reported: Congestive heart failure, cardiomyopathy, decreased ejection fraction in non-MS patients previously treated with potentially cardiotoxic agents[Ref]


Very common (10% or more): Arthralgia (12%), pain in extremity (12%), back pain (12%)
Common (1% to 10%): Chills, muscular weakness, muscle spasms, myalgia, neck pain, arthralgia, skeletal pain, back pain
Uncommon (0.1% to 1%): Leg pain, hypertonia, muscle spasms
Frequency not reported: Arthritis or worsening arthritis, bone fracture, myositis, muscle atrophy, osteomyelitis, polymyositis, skeletal pain[Ref]


Common (1% to 10%): Anxiety, confusion, depression, somnolence
Uncommon (0.1% to 1%): Suicidal behavior or ideation, depersonalization, personality disorder, abnormal thinking, nervousness, apathy[Ref]


Very common (10% or more): Rash (53%), urticaria (16%), pruritus (14%)
Common (1% to 10%): Dermatitis, erythema, hyperhidrosis, bullous eruption, erythematous rash
Uncommon (0.1% to 1%): Maculopapular rash, skin disorder[Ref]


Very common (10% or more): Thyroid gland disorders (13%)[Ref]


Frequency not reported: Hyperbilirubinemia, hepatic failure, hepatocellular damage, hypoalbuminemia, biliary pain[Ref]


Very common (10% or more): Anorexia
Common (1% to 10%): hyponatremia, hypocalcemia, weight decrease, dehydration, thirst
Uncommon (0.1% to 1%): Hypokalemia, diabetes mellitus aggravated
Frequency not reported: Thyroid disorder, fluid overload[Ref]


Frequency not reported: Malignancies (e.g., malignant lymphoma, malignant testicular neoplasm, prostatic cancer, plasma cell dyscrasias, secondary leukemia, squamous cell carcinoma)[Ref]


Very common (10% or more): Urinary tract infection (19%)
Common (1% to 10%): Blood in urine, abnormal uterine bleeding
Uncommon (0.1% to 1%): Impotence, urinary incontinence, urine flow decreased, polyuria, cystitis
Frequency not reported: Cervical dysplasia[Ref]


Very common (10% or more): Pyrexia (29%), fatigue (18%), flushing (10%)
Common (1% to 10%): Asthenia[Ref]


Uncommon (0.1% to 1%): Renal function abnormal
Frequency not reported: Acute renal failure[Ref]


Common (1% to 10%): Conjunctivitis
Uncommon (0.1% to 1%): Endophthalmitis[Ref]


Uncommon (0.1% to 1%): Allergic reaction
Frequency not reported: Anaphylactoid reaction[Ref]


Uncommon (0.1% to 1%): Infusion site bruising, infusion site dermatitis, infusion site pain
Frequency not reported: Infusion reactions[Ref]


1. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

2. "Product Information. Campath (alemtuzumab)" Berlex, Richmond, CA.

3. Cerner Multum, Inc. "Australian Product Information." O 0

4. Poynton CH, Mort D, Maughan TS "Adverse reactions to Campath-1H monoclonal antibody [letter; comment]." Lancet 341 (1993): 1037

5. Rai KR, Freter CE, Mercier RJ, et al. "Alemtuzumab in previously treated chronic lymphocytic leukemia patients who also had received fludarabine." J Clin Oncol 20 (2002): 3891-7

6. Ghobrial IM, Otteman LA, White WL "An EBV-positive lymphoproliferative disorder after therapy with alemtuzumab." N Engl J Med 349 (2003): 2570-2; discussion 2570-2

Some side effects of alemtuzumab may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.