Cross-Sectional Assessment of Pharmacy Students’ Knowledge and Perception of Drug-Drug Interactions with Over the Counter Products

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Rana Abutaima


Drug Interactions, Over the counter medicines (OTC), Pharmacy Education


Background: Self-medication with over-the-counter products has dramatically increased following coronavirus disease of 2019 pandemic. For safe public use of these products, Pharmacy and Doctor of Pharmacy students are expected to have proper knowledge and perception towards these products dispensing and associated interactions. Objectives: A cross-sectional survey was developed to assess Pharmacy and Doctor of Pharmacy students’ knowledge and perception towards drug interactions of over the counter products. Methods:  Data were collected using a self-administered questionnaire and statistically analyzed. Descriptive statistics (frequency) were analyzed for participants’ demographics. Multivariable logistic regression analysis was used to determine the association between over the counter products and relevant interactions with medications to treat chronic illnesses. A P value < 0.05 was used to determine statistical significance. Results: Responses were 411 and only 389 were included. 76.6% were studying Bachelor of Pharmacy and 86.1% were on a regular study program. Recipients of Pharmacy training were 65.3% and 62.0% of participants studied over the counter course. Orphenadrine muscle relaxant was the mostly identified over the counter product (n= 339, 87.1%). Majority of students (n= 345, 88.7%) consider that OTC products help improving conditions being dispensed for. Bridging students and those who studied over the counter course showed significant knowledge in drug interactions compared to regular-program students and those who did not complete the course (P= 0.004, P< 0.001, respectively). Of the 389 respondents, 79.9% and 79.2% considered hydrochlorothiazide and metformin as over the counter products, respectively, compared to 54.0% for amoxicillin. Conclusion:  College of Pharmacy students showed moderate knowledge towards drug interactions of over the counter products. This warrant the necessity to shed the light on inclusion of drug interactions Pharmacy curriculum and to include reliable applications to help in checking drug interactions before dispensing and to emphasize on distinguishing between prescription and non-prescription medications.

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