People who take herbal products or food supplements may experience unexpected changes in the coagulation system. Any person with unexpected coagulation findings should be queried on intake of herbal or dietary products.



(1) easy bruisability

(2) prolonged oozing

(3) unexpected coagulation test finding

Effects Seen

Possible Explanations

prolonged bleeding time, evidence of platelet dysfunction

fish oil, salicylates, NSAID additives

increased prothrombin time (PT)

furanocoumarins in green plants

erratic response or failure to respond as expected to coumadin anticoagulation

vitamin K from green plants


Factors determining effect:

(1) comorbid medical conditions

(2) concurrent prescribed and OTC medications

(3) number of different types of supplements

(4) dose of the supplements


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