Nature and frequency of drug-related problems in self-medication (over-the-counter drugs) in daily community pharmacy practice in Germany

Purpose: To quantify drug-related problems (DRPs) in self-medication (over-the-counter [OTC] drug use) identified by community pharmacists (CPs) in Germany at the time the drug is dispensed.

Methods: One hundred CPs were asked to document 100 consecutive customers presenting symptoms or requesting OTC drugs using a standardized documentation form. The number of 10,000 encounters seemed reasonable to evaluate the set objective. For each encounter, data such as age, sex, and first or repeated request and the availability of a patient file in the pharmacy including drug history were documented. Furthermore, identified DRPs, problem descriptions, and solutions were documented. Data were transcribed electronically, coded, checked for validity, and analyzed.

Results: In total, 109 CPs documented 12,567 encounters identifying DRPs in 17.6% of all cases. Four indications comprised more than 70% of all DRPs: pain, respiratory, gastrointestinal, and skin disorders. Four DRPs were responsible for almost 75% of all DRPs identified: self-medication inappropriate (29.7%), requested product inappropriate (20.5%), intended duration of drug use too high including abuse (17.1%), and wrong dosage (6.8%). If a drug history was available, significantly more cases with wrong dosage (p < 0.05) and drug-drug interactions (p < 0.001) were detected. All patients with identified DRPs were counseled accordingly. Furthermore, the most frequent interventions were referral to a physician (39.5%) and switching to a more appropriate drug (28.1%).

Conclusions: In nearly one of five encounters, a direct pharmacist-patient interaction about self-medication revealed relevant DRPs. Having access to patient files including data on prescription and OTC drugs may increase patient safety.