Glivec (Imatinib)

Glivec (imatinib) is indicated for several malignancies that involve abnormal tyrosine‑kinase activity and is prescribed as part of targeted therapy regimens.

• Chronic myeloid leukemia (CML), particularly in newly diagnosed patients or those with resistance to prior therapy.
• Philadelphia chromosome‑positive acute lymphoblastic leukemia (Ph+ ALL) in adults and eligible pediatric patients.
• Gastrointestinal stromal tumor (GIST) that harbors KIT or PDGFRA activating mutations.
• Dermatofibrosarcoma protuberans (DFSP) when surgical options are limited.
• Systemic mastocytosis with an activating KIT mutation, as part of disease‑modifying treatment.

Adverse reactions to Glivec vary in frequency and severity; they are documented in clinical studies and post‑marketing reports.

Common

• Nausea, vomiting, or loss of appetite.
• Diarrhea or abdominal discomfort.
• Edema, especially peripheral swelling.
• Fatigue or generalized weakness.
• Skin rash or pruritus.

Serious

• Hepatotoxicity manifested by elevated liver enzymes.
• Severe neutropenia or thrombocytopenia increasing infection or bleeding risk.
• Cardiac dysfunction such as left ventricular failure.

Before initiating Glivec, clinicians consider several safety factors to minimize risk.

• Baseline and periodic liver function tests to monitor for hepatotoxicity.
• Complete blood counts to detect myelosuppression early.
• Assessment of cardiac function in patients with pre‑existing heart disease.
• Caution in patients with renal impairment; dose adjustment may be required.
• Pregnancy and lactation status should be evaluated, as safety data are limited.
• Patients should be advised to report signs of infection, bleeding, or severe rash promptly.

Glivec can interact with other medicines, affecting its concentration or toxicity.

Avoid

• Strong CYP3A4 inhibitors (e.g., ketoconazole, clarithromycin) that may raise imatinib levels.
• Concurrent use with other tyrosine‑kinase inhibitors due to overlapping toxicity.

Use with caution

• CYP3A4 inducers (e.g., rifampin, phenytoin) that may reduce efficacy.
• Anticoagulants such as warfarin, which may have altered INR.
• Proton‑pump inhibitors that could affect gastric pH and absorption.
• Vaccines, especially live attenuated, due to potential immunosuppression.