• AIMS AND OBJECTIVES : This survey aimed at assessing the perceptions of physicians regarding the appropriateness of prescribing herbal medicines (HM), their prescribing patterns and their knowledge regarding the interaction between HM and conventional drugs. BACKGROUND : No data are currently available in Lebanon concerning the frequency of HM prescription and indications. HM poorly prescribed can affect the overall quality of health among patients taking conventional drugs. METHODS : This descriptive survey study was conducted in the Greater Beirut area in Lebanon during May-June 2009. All Primary Health Care (PHC) physicians in private community-based solo practice were identified from the Lebanese Order of Physicians listing, contacted and invited to participate. Those who agreed had to complete a pre-piloted face-to-face questionnaire. RESULTS : Of two hundred twelve participating physicians, 45% routinely prescribed HM to their patients. Between 64 to 67% prescribers believed that HM have more benefits, faster results and fewer side effects than conventional drugs. In addition, 58% thought that HM were less expensive, and 76% that they were easier to take than conventional drugs. More importantly, in a series of eight questions concerning the physicians' knowledge about the possible mechanism of drug-herb interactions, the general tendency was towards poor knowledge. CONCLUSIONS : A good percentage of PHC physicians who routinely prescribe HM do not know their mechanism of action or their possible interactions with the conventional drugs. Knowledge about mechanism of drug-herb interactions should be an integral part of the medical curriculum. RELEVANCE TO CLINICAL PRACTICE : The knowledge about HM should be an integral part of the medical curriculum as they are frequently prescribed by PHC physicians.