Imatinib Mesylate
Cytostatic · Bcr-Abl tyrosine kinase inhibitor
Indications
Philadelphia chromosome (Bcr-Abl) positive chronic myeloid leukaemia in newly diagnosed patients where bone marrow transplant is not considered as 1st line treatment, or in patients in chronic phase after failure of interferon alfa, or in patients in accelerated phase or blast crisis. Kit (CD117) positive unresectable and/or metastatic malignant gastrointestinal stromal tumours (GIST).
Dosage
Chronic phase CML: Adults: 400 mg once daily with meal and large glass of water. Accelerated phase CML or blast crisis, Adults: 600 mg once daily with meal and large glass of water. GIST: Adults: 400 mg once daily with meal and large glass of water. Children: Not recommended. Chronic phase CML: Children: Under 3 yr, not recommended; over 3 yr, 260 mg/m² daily as a single dose or in two divided doses; max 400 mg daily. Advanced phase CML: Children: Under 3 yr, not recommended; over 3 yr, 340 mg/m² daily as a single dose or in two divided doses; max 600 mg daily.
Adverse Effects
Severe non-haematological reactions; discontinue until resolved. Raised bilirubin or transaminases; withhold until levels <1.5 IULN and <2.5 IULN resp. then reinstate at lower dose. Severe neutropenia or thrombocytopenia; reduce dose or interrupt treatment. GI upset, anorexia, headache, dizziness, taste disturbance, paraesthesia, insomnia, CNS disturbance, conjunctivitis, lacrimation, pleural effusion, epistaxis, myalgia, cramps, skin reactions, dry mouth, pyrexia, fatigue, weakness, rigour. Fluid retention, oedema, wt. gain; investigate unexpected rapid wt. gain, blood dyscrasias, dysgeusia, hypoaesthesia, flushing, haemorrhage, alopecia, cough, dyspnoea, musculoskeletal pain, spasm and inflammation, eye disorders, increased liver enzymes. Reports of gastric antral vascular ectasia.
Risk Factor (Pregnancy/Lactation)
Pregnancy: Positive evidence of risk: Use only when no safer alternative exists for a serious problem. Lactation: Contraindicated or not recommended. Precautions: Hepatic or severe renal impairment, history of cardiac disease. Monitor blood counts, liver enzymes, body-wt, renal function and for heart failure regularly. Contraception must be used. Raised bilirubin or transaminases. Minimize UV exposure. Monitor growth in children. Investigate unexpected rapid wt gain. Risk of tumour lysis syndrome; correct dehydration and hyperuricaemia before starting. Test for HBV Severe neutropenia or thrombocytopenia; reduce dose or interrupt treatment. Severe non-haematological reactions.
Interactions
Warfarin, drugs that affect or are affected by CYP3A4 or CYP2D6, paracetamol, levothyroxine, phenytoin, phenobarbital, carbamazepine, rifampin, L-asparaginase, levothyroxine.
Advice to Patient
Take with meals. Swallow whole with a glass of water. If you are unable to swallow, disperse it in a glass of water or apple juice. 50 mL liquid for a 100 mg tablet and 200 mL liquid for a 400 mg tablet is approximately required. Stir with a spoon and drink immediately after tablet is completely dispersed. Contact prescriber if there is difficulty in breathing, cough, wheezing, swelling of extremities, chest pain, palpitations, muscle pain, bone pain, tremors, skin rash, weight gain >5 lb, cramps, easy bruising or bleeding, constant fatigue or weakness, blood in vomit/stool/urine, dark coloured stool, bleeding from mouth, severe persistent abdominal disturbances. Take missed dose as soon as possible unless it is almost time for the next dose. Do not take double dose. Do not take alcohol during treatment. Take sufficient amount of fluids (2-3 litres per day) to maintain hydration, unless…
Pharmacokinetics
Absorption: Rapid. Metabolism: Hepatic. Bioavailability: 98%; may be decreased in patients who have had gastric surgery. Half-life elimination: Adults: Parent drug: Approx. 18 hours; N-desmethyl metabolite: Approx. 40 hours; Children: Parent drug: Approx. 15 hours. Time to peak: 2 to 4 hours. Excretion: Feces (68% primarily as metabolites, 20% as unchanged drug); urine (13% primarily as metabolites, 5% as unchanged drug).
Brands with this active ingredient
Compiled by Healify Pharmacy from published drug references. How we compile it →
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