Evaluation of potential drug-drug interactions in medical wards of a referral university hospital in southern part of Iran: a retrospective observational study

Document Type : Original Article


1 Department of Clinical Pharmacy, School of Pharmacy, Shiraz University of Medical Sciences, Shiraz, Iran.

2 Student research committee, School of Pharmacy, Shiraz University of Medical Sciences, Shiraz, Iran.

3 Department of Clinical Pharmacy, School of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran



Introduction: Drug-drug interactions impose several financial and medical burden on medical system and can lead to various health problems. The aim of this study was to investigate the incidence of Potential Drug-Drug Interactions (PDDIs) and its related factors in patients admitted to a large university hospital in southern part of Iran.
Method: A retrospective observational study was conducted in neurology, infectious and endocrinology wards of a tertiary care teaching hospital, Shiraz, Iran. PDDIs were identified using Lexi-InteractTM Online database. The relationship betweenpatient’s age, gender, comorbidity, number of medications,administration of high risk drugs, physician's university rank and scientific level, type of hospital wardand PDDIs has been studied using logistic regression analysis.
Result and conclusion: Totally 600 patients were evaluated in our study. A total number of 5051 interactions were identified. 89.5% of patients experienced at least one interaction regardless of the severity. The most frequent interaction was reported to be class C (84.63%) interaction. According to our results, number of medications, administration of high risk drugs, and type of hospital ward were reported as significant risk factors for the incidence of PDDIs.
Discussion: This study suggest that the prevalence of PDDIs is still high even in a large university hospital.Using modern medical systems), regular monitoring of patients' medications,and paying special attention to patients who are elderly or have certain diseases could help to minimize drug interactions. Moreover, the role of pharmacist should not be ignored whom are the best professionals for preventing, monitoring and managing drug interactions.


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