Imatinib Calcium-channel blockers

IMATINIB CALCIUM CHANNEL BLOCKERS t plasma concentrations of imatinib when co-administered with diltiazem, nifedipine and verapamil, t risk of toxicity (e.g. abdominal pain, constipation, dyspnoea) and of neurotoxicity (e.g. taste disturbances, dizziness, headache, paraesthesia, peripheral neuropathy) Due to inhibition of hepatic metabolism of imatinib by the CYP3A4 isoenzymes by diltiazem Monitor for clinical efficacy and for the signs of toxicity listed, along with convulsions, confusion and signs of oedema (including pulmonary oedema). Monitor electrolytes and liver function, and for cardiotoxicity... 

Imatinib increases serum tacrolimus levels and is therefore predicted to increase ciclosporin levels. Imatinib may also increases the levels of some benzodiazepines (e.g. midazolam), some calcium-channel blockers (e.g. nifedipine), oestrogens, paracetamol, pimozide, and warfarin. In one case lansoprazole was suspected to have raised imatinib levels. 

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