Purpose Problem-oriented drug information (POD) is a service in which health professionals provide evidencebased answers to clinical questions posed by physicians. The objective of this study was to evaluate the user satisfaction and clinical impact of POD, to investigate predictors for use and to examine the kind of sources physicians search before applying for POD. Methods To evaluate POD, a questionnaire was distributed with problem-oriented answers sent from a drug information centre to physicians during the period of April 2006 to March 2007. Results Of 197 questionnaires, 183 (93%) were returned. The information from the POD service was highly valued by the physicians, and 90% of the answers led to reported impact on clinical practice in the specific clinical situation. Furthermore, 74% of the answers were intended to be used in a wider context either for future patients (67%) or for dissemination to colleagues (51%). Secondary-care physicians more often than general practitioners (GPs) used the information for dissemination to colleagues (63 vs. 39%, P=0.0008), while GPs more often used the answer to support patient information (88 vs. 70%, P=0.0029). The most prominent motive for applying for POD was a request for evidencebased information (78%), and the service was used to overcome barriers to practicing evidence-based medicine such as lack of time (36%), skills for searching (26%), and appraising the literature (13%). Before inquiring, 74% of the physicians had tried other information sources; the most frequent sources used were a drug reference (68%) and consulting a colleague (24%). Secondary-care physicians reported fewer barriers than GPs when seeking information, and secondary-care physicians searched other sources more often than GPs before contacting the service (81 vs. 67%, P=0.031). Conclusion POD represents a useful source for acquiring evidence-based drug information by physicians. POD is highly valued by the users. It was reported to have an impact on clinical practice for the specific patient but is also intended to be used in a wider context for future patients or for dissemination to colleagues. GPs' and secondary-care physicians' use of POD differs with GPs having more focus on patient information and secondary-care physicians having more focus on dissemination of the information to colleagues.