Impact of educational intervention on the pattern and incidence of potential drug-drug interactions in Nepal

  • Durga Bista
  • Archana Saha
  • Pranaya Mishra
  • Subish Palaian
  • Pathiyil R. Shankar
Keywords: Drug Interactions, Inpatients, Education, Continuing, Nepal


Objective: To study the impact of educational intervention on the pattern and incidence of potential drug-drug interactions (DDIs).

Method: All patients admitted to Internal Medicine wards of Manipal Teaching Hospital during the study period were included. Patient details were collected using a patient profile form and the datum from the filled forms was analyzed using Micromedex electronic database. An intervention was carried out through a presentation during clinical meeting and personal discussion. The target groups for the intervention included doctors and the nurses.

Results: Altogether 435 patients during preintervention and 445 during postintervention were studied. The incidence of potential DDIs was 53% (preintervention) and 41% (postintervention) [chi-square =11.27, p=0.001]. The average number of drugs per patient was 8.53 (pre-intervention) and 7.32 (post-intervention) [t=3.493, p=0.001]. Sixty-four percent of the potential DDIs were of ‘Moderate’ type and 58% had a ‘Delayed’ onset in both the phases. Seventy percent of the potential DDIs during the pre-intervention phase and 61% during post-intervention phase had a ‘Good’ documentation status. Pharmacokinetic mechanism accounted for 45% of the potential DDIs during pre-intervention and 36% in the post-intervention phase. Cardiovascular drugs accounted for 36% of the potential DDIs during pre-intervention and 33.2% during post-intervention phase. Furosemide was the high risk drug responsible for DDIs in both phases. The most common potential DDIs observed were between amlodipine and atenolol (4.82%) (preintervention) and frusemide and aspirin (5.20%) (postintervention).

Conclusion: There was an association between potential DDIs and age, sex, and polypharmacy.


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How to Cite
Bista D, Saha A, Mishra P, Palaian S, Shankar PR. Impact of educational intervention on the pattern and incidence of potential drug-drug interactions in Nepal. Pharm Pract (Granada) [Internet]. 2009Dec.14 [cited 2020Dec.4];7(4):242-7. Available from:
Original Research