Enzyme inhibitor or reducer of CYP2C8 eg gemfibrozil, rifampicin. Adrenaline (epinephrine), aminogluthethimide, chlorpromazine, corticosteroids, diazoxide, OCs, rifamycins, thiazide diuretics. ACE inhibitors, alcohol, allopurinol, azapropazone, phenylbutazone, salicylates, azole antifungals, chloramphenicol, cimetidine, clofibrate & related compd, coumarin anticoagulants, halofenate, heparin, MAOIs, octreotide, ranitidine, sulfinpyrazone, sulfonamides, tetracyclines, TCAs, thyroid hormones.