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Published on: February 28, 2012
Probable interaction between warfarin and a toothache solution containing Piper longum L. leading to ischemic stroke:
Jing Huang1, Chenchen Sun2, Guodong Lou3
1Department of Pharmacy, The First Affiliated Hospital of Ningbo University, Zhejiang Ningbo, 315020, China; Department of Pharmacy, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310016, China.
Ethnopharmacological Relevance:
Both warfarin and Chinese patent medicine (CPM) are frequently prescribed medications that may have a potential interaction that can go unnoticed.
Aim Of The Study:
To report a clinical case of a probable interaction between warfarin and a toothache solution containing Piper longum L., which led to ischemic stroke.
Materials And Methods:
We collected data on the clinical case of acute ischemic stroke involving warfarin and the suspected drugs. We performed drug interaction assessment using the Lexicomp® Online™ database and literature search. The Drug Interaction Probability Scale (DIPS) was used to assess the causal relationship between potential drug interactions and the occurrence of ischemic stroke.
Results:
Fluctuations in the international normalized ratio (INR) were accompanied by ischemic stroke in a patient with a mechanical heart valve taking warfarin. Causal assessment showed a probable interaction between the interaction of warfarin and a toothache solution containing Piper longum and the ischemic stroke.
Conclusions:
The potential interaction between warfarin and Piper longum should be recognized to prevent adverse outcomes in patients receiving warfarin therapy.
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