Fatal haemopericardium and gastrointestinal haemorrhage due to possible interaction of cranberry juice with warfarin.
We report a case of fatal internal haemorrhage in an elderly man who consumed only cranberry juice for two weeks while maintaining his usual dosage of warfarin. We propose that naturally occurring compounds such as flavonoids, which are present in fruit juices, may increase the potency of warfarin by competing for the enzymes that normally inactivate warfarin. While traditionally regarded as foodstuffs, consumption of fruit juices should be considered when patients develop adverse drug reactions.
Griffiths
A P
AP
Department of Histopathology, Morriston Hospital, Swansea SA6 6NL, UK. paul.griffiths@swansea-.tr.wales.nhs.uk
Beddall
A
A
Pegler
S
S
D000368:Aged; D000925:Anticoagulants / Q000009:adverse effects* / Q000378:metabolism; D001628:Beverages / Q000009:adverse effects; D017809:Fatal Outcome; D005419:Flavonoids / Q000009:adverse effects; D018565:Food-Drug Interactions; D006471:Gastrointestinal Hemorrhage / Q000139:chemically induced*; D006801:Humans; D008297:Male; D010490:Pericardial Effusion / Q000139:chemically induced*; D008517:Phytotherapy / Q000009:adverse effects; D029799:Vaccinium macrocarpon / Q000009:adverse effects* / Q000378:metabolism; D014859:Warfarin / Q000009:adverse effects* / Q000378:metabolism
D000925:Anticoagulants; D005419:Flavonoids; D014859:Warfarin