International Journal of Clinical Pharmacy

, Volume 39, Issue 3, pp 560–568 | Cite as

A survey of attitudes, practices, and knowledge regarding drug–drug interactions among medical residents in Iran

  • Ehsan Nabovati
  • Hasan Vakili-ArkiEmail author
  • Zhila Taherzadeh
  • Mohammad Reza Saberi
  • Ameen Abu-Hanna
  • Saeid EslamiEmail author
Research Article


Background When prescribing medications, physicians should recognize clinically relevant potential drug–drug interactions (DDIs). To improve medication safety, it is important to understand prescribers’ knowledge and opinions pertaining to DDIs. Objective To determine the current DDI information sources used by medical residents, their knowledge of DDIs, their opinions about performance feedback on co-prescription of interacting drugs. Setting Academic hospitals of Mashhad University of Medical Sciences (MUMS) in Iran. Methods A questionnaire containing questions regarding demographic and practice characteristics, DDI information sources, ability to recognize DDIs, and opinions about performance feedback was distributed to medical residents of 22 specialties in eight academic hospitals in Iran. We analyzed their perception pertaining to DDIs, their performance on classifying drug pairs, and we used a linear regression model to assess the association of potential determinants on their DDI knowledge. Main Outcome Measure prescribers’ knowledge and opinions pertaining to DDIs. Results The overall response rate and completion rate for 315 distributed questionnaires were 90% (n = 295) and 86% (n = 281), respectively. Among DDI information sources, books, software on mobile phone or tablet, and Internet were the most commonly-used references. Residents could correctly classify only 41% (5.7/14) of the drug pairs. The regression model showed no significant association between residents’ characteristics and their DDI knowledge. An overwhelming majority of the respondents (n = 268, 95.4%) wished to receive performance feedback on co-prescription of interacting drugs in their prescriptions. They mostly selected information technology-based tools (i.e. short text message and email) as their preferred method of receiving feedback. Conclusion Our findings indicate that prescribers may have poor ability to prevent clinically relevant potential DDI occurrence, and they perceive the need for performance feedback. These findings underline the importance of well-designed computerized alerting systems and delivering performance feedback to improve patient safety.


Drug–drug interaction Information sources Iran Medication knowledge Performance feedback Prescribers’ attitude 



The authors would like to acknowledge Prof. Daniel C. Malone, Dr. Yu Ko and their colleagues for providing us the access to the long version of the survey questionnaire. We would like to thank the experts who were consulted for the revision of the questionnaire. We would also like to extend our appreciation to the medical residents who participated in the survey.


This study was supported by a grant from Mashhad University of Medical Sciences Research Council.

Conflicts of interest

The authors declare that they have no conflict of interest.


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Copyright information

© Springer International Publishing 2017

Authors and Affiliations

  • Ehsan Nabovati
    • 1
    • 2
  • Hasan Vakili-Arki
    • 3
    Email author
  • Zhila Taherzadeh
    • 4
    • 5
  • Mohammad Reza Saberi
    • 6
  • Ameen Abu-Hanna
    • 9
  • Saeid Eslami
    • 7
    • 8
    • 9
    Email author
  1. 1.Health Information Management Research CenterKashan University of Medical SciencesKashanIran
  2. 2.Department of Health Information Management and Technology, School of Allied Health ProfessionsKashan University of Medical SciencesKashanIran
  3. 3.Student Research Committee, Department of Medical Informatics, Faculty of MedicineMashhad University of Medical SciencesMashhadIran
  4. 4.Targeted Drug Delivery Research CenterMashhad University of Medical SciencesMashhadIran
  5. 5.Neurogenic Inflammation Research CenterMashhad University of Medical SciencesMashhadIran
  6. 6.Medical Chemistry Department, School of PharmacyMashhad University of Medical SciencesMashhadIran
  7. 7.Pharmaceutical Research Center, School of PharmacyMashhad University of Medical SciencesMashhadIran
  8. 8.Department of Medical Informatics, Faculty of MedicineMashhad University of Medical SciencesMashhadIran
  9. 9.Department of Medical Informatics, Academic Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands

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