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.


Download data is not yet available.


1. Lee A, Stockley IH. Drug interactions In: Walker R, Edwards C. Clinical Pharmacy and Therapeutics. 3rd edition. Churchill Livingstone, Philadelphia 2003: 21-31.

2. Chobanian AV, Bakris GL, Black HR, Cushman WC, Green LA, Izzo JL Jr, Jones DW, Materson BJ, Oparil S, Wright JT Jr, Roccella EJ; National Heart, Lung, and Blood Institute Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure; National High Blood Pressure Education Program Coordinating Committee. The seventh report of the joint national committee on prevention, detection, evaluation, and treatment of high blood pressure. The JNC 7 report. J Am Med Assoc. 2003;289:2560-2572.

3. Boston Collaborative Drug Survelliance Program: Adverse drug interactions. J Am Med Assoc. 1972;220:1238-1239.

4. Classen DC, Pestotnick SL, Evans RS, Bukke JP. Computerized surveillance of adverse drug events in hospital patients. J Am Med Assoc. 1991;266:2847-2851.

5. Grymonpre RE, Mitenko PA, Sitar DS, Aoki FY, Montgomery PR. Drug-associated hospital admissions in older medical patients. J Am Geriatr Soc. 1988;36:1092-1098.

6. Stockley IH. Drug interaction: a source book of adverse interaction, their mechanisms, clinical importance and management.5th ed. Pharmaceutical Press, London 1999.

7. Smith JW, Seild L G, Cluff L E. Studies on the epidemiology of adverse drug reactions. V. Clinical factors influencing susceptibility. Ann Intern Med. 1969;65:629.

8. Joshi MP, Sugimoto T, Santoso B. Geriatric prescribing in the medical wards of a teaching hospital in Nepal. Pharmacoepidemiol Drug Saf. 1997;6:417-421.

9. Thomson Micromedex, Greenwood Village, Colorado (Edition expires [6/2006])

10. Jankel CA, Fitterman LK. Epidemiology of drug-drug interactions as a cause of hospital admissions. Drug Saf. 1993;9:55-59.

11. Leape LL, Brennan TA, Laird N, Lawthers AG, Localio AR, Barnes BA, Hebert L, Newhouse JP, Weiler PC, Hiatt H. The nature of adverse events in hospitalized patients: results of the Harvard Medical Practice Study II. N Engl J Med. 1991;324(6):377-384.

12. Merlo J, Liedholm H, Lindblad U, Björck-Linné A, Fält J, Lindberg G, Melander A. Prescriptions with potential drug interactions dispensed at Swedish pharmacies in January 1999: cross sectional study. BMJ. 2001;323:427-428.

13. Nagavi BG, Singhal R. Drug interactions in prescription from selected Indian community pharmacies. J Pharm Pract Res. 2005;35:332.

14. Bergendal L, Friberg A, Schaffrath AM. Potential drug-drug interactions in 5,125 mostly elderly out-patients in Gothenburg, Sweden. Pharm World Sci. 1995;17:152-157.

15. Stewart RB, Cooper JW. Polypharmacy in the aged. Practical solutions. Drugs Aging. 1994;4:449-461.

16. Biorkman IK, Fastbom J, Schmidt IK, Bernsten CB. Drug-drug interactions in the elderly. Ann Pharmacother. 2002;36:1675-1681.

17. Goldberg RM, Mabee J, Chan L, Wong S. Drug-drug and drug-disease interactions in the ED: analysis of a high-risk population. Am J Emerg Med. 1996;14;447-450.

18. Egger SS, Drewe J, Schlienger RG. Potential drug-drug interactions in the medication of medical patients at hospital discharge. Eur J Clin Pharmacol. 2003; 58:773-778.

19. Oeser DE, Polansky M, Thomas NP, Varon J. Incidence of major drug interactions and associated adverse drug events in a surgical intensive care unit. Internet J Pharmacol. 2003;2.

20. Johnson MD, Newkirk G, White JR Jr. Clinically significant drug interactions: what you need to know before writing prescriptions. Postgrad Med. 1999;105:193-206.

21. Chadwick B, Waller DG, Edwards JG. Potentially hazardous drug interactions with psychotropics. Advances in Psychiatric treatment. 2005;11:440-449.

22. Hussar DA. Drug interaction. In: Gennaro, Marderosian AHD, Hanson GR et al. Remington The science and practice of pharmacy. Philadelphia: Lippincott Williams & Wilkins, 2000: 1746-1761.

23. Pirmohamed M, James S, Meakin S, Green C, Scott AK, Walley TJ, Farrar K, Park BK, Breckenridge AM. Adverse drug reactions as cause of admission to hospital: prospective analysis of 18 820 patients. BMJ. 2004;329:15-19.

24. Doucet J, Chassagne P, Trivalle C, Landrin I, Pauty MD, Kadri N, Ménard JF, Bercoff E. Drug-drug interactions related to hospital admissions in older adults: a prospective study of 1000 patients. J Am Geriatr Soc. 1996;44:944-948.

25. Durrence CW 3rd, DiPiro JT, May JR, Nesbit RR Jr, Sisley JF, Cooper JW. Potential drug interactions in surgical patients. Am J Hosp Pharm. 1985;42:1553-1556.
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 2019Jun.16];7(4):242-7. Available from:
Original Research