Abstract
Introduction: There is a general perception of the safety of use for
herbal medicines. Moreover, limited studies addressed herbal-drug
interactions (HDI). The Saudi Food and Drug Authority (SFDA) established
Herbal-Drug Interaction project to detect and assess HDIs to ensure
safety. The aim is to detect safety signals and assess them based on
available evidence. Methods: First, a number of SFDA-registered herbal
products (n=30) were selected and prioritized based on commonly used
herbs. Second, reported HDIs were retrieved from the World Health
Organization (WHO) global database of individual case safety reports
(VigiBase), AdisInsight® and Natural Medicines database. We excluded
non-registered drugs by SFDA and labeled interactions in the product
information of SFDA, the U.S. Food and Drug Administration (FDA), and
European medicines agency (EMA). Finally, a comprehensive evaluation of
potential HDIs using several evidence sources; literature, global cases,
local cases and other relevant documents. The Drug Interaction
Probability Scale (DIPS) scale used to assess the probability of a
causal relationship between interacting herb-drug and the event.
Results: The search yielded 566 potential signals, and 41 had published
evidence and referred for assessment. The assessment results using DIPS
were; 22 possible (53.6 %), 7 probable (17%), and 12 doubtful (29.2%)
interactions. Recommendation was to include probable HDIs in the product
information, including Turmeric-Tacrolimus, Etoposide-Echinacea, Ginkgo
Biloba-Ibuprofen, Green Tea-Warfarin, and Licorice-Thiazides
interactions. Conclusion: The HDI project assessed in the screening and
identification of potential herbal-drug interactions. The action plan of
this project can be used in post-marketing activities to identify
potential drug interactions.