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Gemtuzumab Side Effects

For the Consumer

Applies to gemtuzumab: intravenous powder for solution

In addition to its needed effects, some unwanted effects may be caused by gemtuzumab. In the event that any of these side effects do occur, they may require medical attention.

If any of the following side effects occur while taking gemtuzumab, check with your doctor or nurse immediately:

More common
  • Black, tarry stools
  • bloating or swelling of the face, arms, hands, lower legs, or feet
  • blood in the stools or urine
  • bluish color of the fingernails, lips, skin, palms, or nailbeds
  • blurred vision
  • burning or stinging of the skin
  • chest pain
  • chills
  • confusion
  • convulsions (seizures)
  • cough or hoarseness
  • cracked lips
  • decrease or increase in urine
  • diarrhea
  • difficulty with swallowing
  • dizziness
  • dry mouth
  • excessive sweating
  • fainting
  • fast or slow heartbeat
  • fever
  • flushed, dry skin
  • fruit-like breath odor
  • headache, sudden and severe
  • heavy, nonmenstrual vaginal bleeding
  • inability to speak
  • increased thirst or hunger
  • irregular heartbeat
  • large, flat, blue, or purplish patches in the skin
  • lightheadedness
  • lower back, joint, or side pain
  • loss of appetite
  • mood changes
  • muscle pain or cramps
  • muscle trembling or twitching
  • nausea or vomiting
  • numbness or tingling in the hands, feet, or lips
  • pain, difficulty, or burning while urinating
  • painful cold sores or blisters on the lips, nose, eyes, or genitals
  • pale skin
  • palpitations
  • persistent bleeding or oozing from puncture sites, mouth, or nose
  • pinpoint red spots on the skin
  • pounding in the ears
  • rapid, shallow breathing
  • rapid weight gain
  • red or purplish patches or spots on the skin
  • severe or continuing dull nervousness
  • shortness of breath
  • slurred speech
  • small red or purple spots on the skin
  • sneezing
  • sore throat
  • sores, ulcers, or white spots on the lips, tongue, or inside the mouth
  • stomachache
  • sweating
  • swelling or inflammation of the mouth, face, fingers, feet, or lower legs
  • swollen glands
  • temporary blindness
  • tightness in the chest
  • tingling of the hands or feet
  • troubled breathing, exertional
  • unexplained nosebleeds
  • unusual bleeding or bruising
  • unusual tiredness or weakness
  • unusual weight gain or loss
  • weakness in the arm or leg on one side of the body, sudden and severe
  • wheezing
  • yellow eyes or skin

Severity: Minor

Some of the side effects that can occur with gemtuzumab may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

More common
  • Acid or sour stomach
  • belching
  • difficulty with moving
  • dry, red, hot, or irritated skin
  • full or bloated feeling or pressure in the stomach
  • heartburn
  • indigestion
  • lack or loss of strength
  • muscle pain or stiffness
  • pain, swelling, or redness in the joints
  • runny, stuffy nose
  • stomach discomfort upset
  • swelling of the abdominal or stomach area
  • trouble with sleeping

For Healthcare Professionals

Applies to gemtuzumab: intravenous powder for injection


Hematologic side effects have included severe myelosuppression which is the major toxicity associated with gemtuzumab. During the treatment phase, grade 3 or 4 thrombocytopenia (99% ), neutropenia (98%), anemia (47%), and bleeding (15%) have been reported. Ecchymosis (13%) has also been reported. Treatment emergent adverse events have included epistaxis (3%), cerebral hemorrhage (2%), disseminated intravascular coagulation (2%), intracranial hemorrhage (2%), and hematuria (1%).[Ref]


General side effects have included fever (85%), chills (73%), asthenia (44%), abdominal pain (37%), headache (35%), sepsis (25%), neutropenic fever (21%), pain (21%), back pain (9%), and enlarged abdomen (9%).[Ref]


Other side effects have included acute infusion related chills (62%), fever (61%), nausea (38%), vomiting (32%), headache (12%), hypotension (11%), hypertension (6%), hypoxia (6%), dyspnea (4%), and hyperglycemia (2%).[Ref]

Acute infusion related events generally occur after the end of the two hour infusion and resolve after two to four hours with supportive therapy of acetaminophen, diphenhydramine, and intravenous fluids.[Ref]


Gastrointestinal side effects have included nausea (70%), vomiting (63%), diarrhea (38%), stomatitis (32%), anorexia (29%), constipation (25%), dyspepsia (11%) and gastrointestinal hemorrhage.[Ref]


Respiratory side effects have included dyspnea (32%), epistaxis (31%), increased cough (20%), pharyngitis (14%), pulmonary physical findings (including rales and changes in breath sounds) (11%), pneumonia (10%), and rhinitis (10%). Severe respiratory events leading to death, including dyspnea, pulmonary hemorrhage, pulmonary infiltrates, pleural effusions, noncardiogenic pulmonary edema, pulmonary insufficiency, hypoxia, and acute respiratory distress syndrome have been reported infrequently.[Ref]


Hepatic side effects have included grade 3 or 4 hyperbilirubinemia (23%), AST abnormalities (17%), ALT abnormalities (9%), concurrent elevations of transaminases (grade 3 to 4) and bilirubin, sinusoidal obstruction syndrome, and hepatic veno-occlusive disease (including fatalities).[Ref]

Hepatic effects are transient and generally reversible.

Sinusoidal obstruction syndrome was characterized by portal hypertension, jaundice, and elevated serum AST levels.[Ref]


Genitourinary side effects have included vaginal hemorrhage (12%) and hematuria (10%).[Ref]


Immunologic side effects have been reported. During the treatment phase, Grade 3 or 4 infections (28%) including opportunistic infections have been reported. Grade 3 or 4 infection related treatment emergent adverse events included sepsis (16%) and pneumonia (7%). Herpes simplex infection (22%) has also been reported.[Ref]


Renal side effects including renal failure secondary to tumor lysis syndrome have been reported.[Ref]


Cardiovascular side effects have included hypertension (20%), hypotension (20%), tachycardia (11%), and hemorrhage (10%).[Ref]


Dermatologic side effects have included local reaction (25%), herpes simplex (22%), rash (22%), petechiae (20%), and peripheral edema (16%).[Ref]

Nervous system

Nervous system side effects have included dizziness (15%), insomnia (15%), and depression (9%).[Ref]


Musculoskeletal side effects have included arthralgia (8%).[Ref]


Metabolic side effects have included hypokalemia (31%), increased lactic dehydrogenase (13%), and hypomagnesemia (10%).[Ref]


Hypersensitivity side effects including anaphylaxis have been reported.[Ref]


1. "Product Information. Mylotarg (gemtuzumab)" Wyeth-Ayerst Laboratories, Philadelphia, PA.

2. Tack DK, Letendre L, Kamath PS, Tefferi A "Development of hepatic veno-occlusive disease after Mylotarg infusion for relapsed acute myeloid leukemia." Bone Marrow Transplant 28 (2001): 895-7

Not all side effects for gemtuzumab may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

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.