Imatinib Side Effects

Medically reviewed by Drugs.com. Last updated on Mar 17, 2025.

Applies to imatinib: oral tablet.

Precautions

It is very important that your doctor check your progress at regular visits to make sure that this medicine is working properly. Blood tests may be needed to check for unwanted effects. Be sure to keep all appointments.

Using this medicine while you are pregnant can harm your unborn baby. Use a highly effective form of birth control (especially if you are a sexually active female patient) during treatment and for 14 days after your last dose to keep from getting pregnant. If you think you have become pregnant while using the medicine, tell your doctor right away.

Serious skin reactions can occur during treatment with this medicine. Check with your doctor right away if you have blistering, peeling, or loosening of the skin, red skin lesions, severe acne or skin rash, sores or ulcers on the skin, or fever or chills while you are using this medicine.

Some serious side effects such as black, tarry stools, severe stomach pain, or vomiting of blood or material that looks like coffee grounds can occur during treatment with this medicine.

While you are being treated with imatinib, and after you stop treatment with it, do not have any immunizations (vaccinations) without your doctor's approval. Imatinib may lower your body's resistance and there is a chance you might get the infection the immunization is meant to prevent. In addition, other persons living in your household should not take oral polio vaccine since there is a chance they could pass the polio virus on to you. Also, avoid persons who have recently taken oral polio vaccine. Do not get close to them and do not stay in the same room with them for very long. If you cannot take these precautions, you should consider wearing a protective face mask that covers the nose and mouth.

Imatinib can temporarily lower the number of white blood cells in your blood, increasing the chance of getting an infection. It can also lower the number of platelets, which are necessary for proper blood clotting. If this occurs, there are certain precautions you can take, especially when your blood count is low, to reduce the risk of infection or bleeding:

• If you can, avoid people with infections. Check with your doctor immediately if you think you are getting an infection or if you get a fever or chills, cough or hoarseness, lower back or side pain, or painful or difficult urination.
• Check with your doctor immediately if you notice any unusual bleeding or bruising, black, tarry stools, blood in the urine or stools, or pinpoint red spots on your skin.
• Be careful when using a regular toothbrush, dental floss, or toothpick. Your medical doctor, dentist, or nurse may recommend other ways to clean your teeth and gums. Check with your medical doctor before having any dental work done.
• Do not touch your eyes or the inside of your nose unless you have just washed your hands and have not touched anything else in the meantime.
• Be careful not to cut yourself when you are using sharp objects such as a safety razor or fingernail or toenail cutters.
• Avoid contact sports or other situations where bruising or injury could occur.

If you are rapidly gaining weight, having chest pain or discomfort, extreme tiredness or weakness, difficulty with breathing, uneven heartbeat, or excessive swelling of the hands, wrist, ankles, or feet, check with your doctor immediately. These may be symptoms of heart problems or your body keeping too much water.

Check with your doctor right away if you have pain or tenderness in the upper stomach, pale stools, dark urine, loss of appetite, nausea, unusual tiredness or weakness, or yellow eyes or skin. These could be symptoms of a serious liver problem.

This medicine may cause slow growth. If your child is using this medicine, the doctor will need to keep track of your child's height and weight to make sure that your child is growing properly.

This medicine may cause a serious type of reaction called tumor lysis syndrome. Your doctor may give you a medicine to help prevent this. Call your doctor right away if you have a decrease or change in urine amount, joint pain, stiffness, or swelling, lower back, side, or stomach pain, a rapid weight gain, swelling of the feet or lower legs, or unusual tiredness or weakness.

This medicine may cause dizziness, drowsiness, or trouble in seeing clearly. Make sure you know how you react to this medicine before you drive, use machines, or do other jobs that require you to be alert or able to see well.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal (eg, St. John's wort) or vitamin supplements.

Serious side effects of imatinib

Along with its needed effects, imatinib 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 immediately if any of the following side effects occur while taking imatinib:

Other side effects of imatinib

Some side effects of imatinib 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:

For healthcare professionals

Applies to imatinib: oral capsule, oral solution, oral tablet.

Cardiovascular adverse events

• Uncommon (0.1% to 1%): Cerebral hemorrhage, palpitations, tachycardia, congestive heart failure, pulmonary edema, hypertension, peripheral coldness, hypotension, Raynaud's phenomenon, chest pain
• Rare (less than 0.1%): Increased intracranial pressure, arrhythmia, atrial fibrillation, cardiac arrest, myocardial infarction, angina pectoris, pericardial effusion
• Frequency not reported: Cerebral edema, pericarditis, cardiac tamponade^[Ref]

Dermatologic

• Very common (10% or more): Dermatitis/eczema/rash (40%)
• Common (1% to 10%): Flushing, pruritus, face edema, dry skin, erythema, alopecia, night sweats, photosensitivity reaction
• Uncommon (0.1% to 1%): Rash pustular, contusion, sweating increased, urticaria, ecchymosis, increased tendency to bruise, hypotrichosis, skin hypopigmentation, dermatitis exfoliative, onychoclasis, folliculitis, petechiae, psoriasis, purpura, skin hyperpigmentation, bullous eruptions
• Rare (less than 0.1%): Acute febrile neutrophilic dermatosis (Sweet's syndrome), nail discoloration, angioneurotic edema, rash vesicular, erythema multiforme, leukocytoclastic vasculitis, Stevens-Johnson syndrome, acute generalized exanthematous pustulosis (AGEP)
• Frequency not reported: Palmoplantar erythrodysesthesia syndrome, lichenoid keratosis, lichen planus, toxic epidermal necrolysis (TEN), drug rash with eosinophilia and systemic symptoms (DRESS)^[Ref]

Gastrointestinal

• Very common (10% or more): Nausea (50%), diarrhea (45%), abdominal pain (37%), constipation (11%), vomiting, dyspepsia
• Common (1% to 10%): Flatulence, abdominal distension, gastroesophageal reflux, dry mouth, gastritis
• Uncommon (0.1% to 1%): Gastroenteritis, stomatitis, mouth ulceration, gastrointestinal hemorrhage, eructation, melena, esophagitis, ascites, gastric ulcer, hematemesis, cheilitis, dysphagia, pancreatitis
• Rare (less than 0.1%): Colitis, ileus, inflammatory bowel disease
• Frequency not reported: Ileus/intestinal obstruction, gastrointestinal perforation, diverticulitis, gastric antral vascular ectasia (GAVE)^[Ref]

Genitourinary

• Uncommon (0.1% to 1%): Urinary tract infection, gynecomastia, erectile dysfunction, menorrhagia, menstruation irregular, sexual dysfunction, nipple pain, breast enlargement, scrotal edema
• Rare (less than 0.1%): Hemorrhagic corpus luteum/hemorrhagic ovarian cyst^[Ref]

Hematologic

• Very common (10% or more): Hemorrhage (29%), neutropenia, thrombocytopenia, anemia
• Common (1% to 10%): Pancytopenia, febrile neutropenia, hemorrhage
• Uncommon (0.1% to 1%): Thrombocythemia, lymphopenia, bone marrow depression, eosinophilia, lymphadenopathy, hematoma, subdural hematoma
• Rare (less than 0.1%): Hemolytic anemia
• Frequency not reported: Thrombosis/embolism^[Ref]

Hepatic

• Common (1% to 10%): Increased hepatic enzymes
• Uncommon (0.1% to 1%): Hyperbilirubinemia, hepatitis, jaundice
• Rare (less than 0.1%): Hepatic failure, hepatic necrosis^[Ref]

Hypersensitivity

• Frequency not reported: Anaphylactic shock^[Ref]

Immunologic

• Very common (10% or more): Influenza (14%)
• Uncommon (0.1% to 1%): Herpes zoster, herpes simplex, cellulitis, sepsis
• Rare (less than 0.1%): Fungal infection
• Frequency not reported: Hepatitis B reactivation^[Ref]

Metabolic

• Very common (10% or more): Weight gain (16%)
• Common (1% to 10%): Anorexia, weight loss
• Uncommon (0.1% to 1%): Hypokalemia, increased appetite, hypophosphatemia, dehydration, gout, hyperuricemia, hypercalcemia, hyperglycemia, hyponatremia, blood creatinine increased, blood creatine phosphokinase increased, blood lactate dehydrogenase increased, blood alkaline phosphatase increased
• Rare (less than 0.1%): Hyperkalemia, hypomagnesemia, blood amylase increased^[Ref]

Musculoskeletal

• Very common (10% or more): Muscle spasm/cramps (49%), musculoskeletal pain (47%), joint pain (31%), myalgia (24%), bone pain (11%)
• Common (1% to 10%): Joint swelling
• Uncommon (0.1% to 1%): Joint and muscle stiffness
• Rare (less than 0.1%): Muscular weakness, arthritis, rhabdomyolysis/myopathy
• Frequency not reported: Avascular necrosis/hip necrosis, growth retardation in children^[Ref]

Nervous system

• Very common (10% or more): Headache (37%), dizziness (19%)
• Common (1% to 10%): Paresthesia, hypoesthesia
• Uncommon (0.1% to 1%): Migraine, syncope, peripheral neuropathy, sciatica, restless leg syndrome, tremor, vertigo
• Rare (less than 0.1%): Seizures^[Ref]

Ocular

• Very common (10% or more): Periorbital edema
• Common (1% to 10%): Eyelid edema, lacrimation increased, conjunctival hemorrhage, conjunctivitis, dry eye, blurred vision
• Uncommon (0.1% to 1%): Eye irritation, eye pain, orbital edema, scleral hemorrhage, retinal hemorrhage, blepharitis, macular edema
• Rare (less than 0.1%): Optic neuritis, cataract, glaucoma, papilledema
• Frequency not reported: Vitreous hemorrhage^[Ref]

Oncologic

• Rare (less than 0.1%): Tumor lysis syndrome
• Frequency not reported: Tumor hemorrhage, tumor necrosis^[Ref]

Other

• Very common (10% or more): Fluid retention/edema (62%, fatigue (39%), pyrexia (18%)
• Common (1% to 10%): Taste disturbance, weakness, pyrexia, anasarca, chills, rigors
• Uncommon (0.1% to 1%): Tinnitus, hearing loss, malaise^[Ref]

Psychiatric

• Very common (10% or more): Insomnia (15%), depression (15%)
• Uncommon (0.1% to 1%): Anxiety, somnolence, memory impairment
• Rare (less than 0.1%): Confusional state^[Ref]

Renal

• Uncommon (0.1% to 1%): Renal pain, hematuria, renal failure acute, urinary frequency increased
• Frequency not reported: Chronic renal failure^[Ref]

Respiratory

• Very common (10% or more): Nasopharyngitis (31%), cough (20%), upper respiratory tract infection (20%), pharyngolaryngeal pain (18%), sinusitis (11%)
• Common (1% to 10%): Dyspnea, epistaxis
• Uncommon (0.1% to 1%): Pneumonia, pleural effusion, pharyngitis
• Rare (less than 0.1%): Pleuritic pain, pulmonary fibrosis, pulmonary hypertension, pulmonary hemorrhage
• Frequency not reported: Acute respiratory failure, interstitial lung disease^[Ref]

See also:

Frequently asked questions

• What to avoid when taking Gleevec?
• Gleevec vs Sprycel vs Tasigna - how do they compare?
• Is there a generic for Gleevec?
• How does Gleevec (imatinib) work?
• Can I take Gleevec while pregnant?

Further information

Imatinib side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer