Phenprocoumon Metformin

The clearance of phenprocoumon was increased by metformin, perhaps because of increased liver blood flow (148). 

One patient had a marked increase in the effects of phenprocou-mon when she stopped taking metformin for a short period, and there is some evidence that metformin increases the metabolism of phenprocoumon. 

Metformin possibly reduces the effects of phenprocoumon by altering blood flow to the liver and interfering with enterohepatic circulation. 

There is some evidence that a small increase in the dosage of phenprocoumon may be necessary if metformin is given but it seems likely that this can be managed with routine anticoagulant monitoring. ... 

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