Tolbutamide Dicumarol

Allopurinol, chloramphenicol, isoniazid Antipyrine, dicumarol, probenecid, tolbutamide... 

Tolbutamide is well absorbed but rapidly metabolized in the liver. Its duration of effect is relatively short, with an elimination half-life of 4-5 hours, and it is best administered in divided doses. Because of its short half-life, it is the safest sulfonylurea for elderly diabetics. Prolonged hypoglycemia has been reported rarely, mostly in patients receiving certain drugs (eg, dicumarol, phenylbutazone, some sulfonamides) that inhibit the metabolism of tolbutamide. 

Hypoglycemics, oral [P] Dicumarol inhibits hepatic metabolism of tolbutamide and chlorpropamide. 

Clinically important, potentially hazardous interactions with aluminum, aminophylline, aspirin, chlorambucil, cimetidine, clarithromycin, cyclophosphamide, cyclosporine, dicumarol, diuretics, docetaxel, estrogens, grapefruit juice, indomethacin, influenza vaccines, itraconazole, ketoconazole, lansoprazole, live vaccines, methotrexate, montelukast, omeprazole, oral contraceptives, pancuronium, phenobarbital, phenytoin, ranitidine, rifampicin, rifampin, timolol, tolbutamide, vitamin A... 

Chaplin H, Cassell M. Studies on the possible relationship of tolbutamide to dicumarol in anticoagulant therapy. AmJMedSci (1958) 235, 706-15. 

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