Published: 2018-03-23

A prospective observational study to evaluate potential drug-drug interactions in patients admitted in intensive care unit, at BRIMS tertiary care hospital in Bidar, India

Shailander Singh, Swetha K.


Background: Drug interaction occurs when presence of one drug affects the activity of another when, both are co-administered. 6-30% of adverse events (AEs) with significant hospitalizations or death are by drug-drug interactions(DDI). There is increased possibility to prevent the potential drug-drug interactions (pDDIs), if their prevalence and pattern are determined accurately before their occurrence. Hence this study aimed to evaluate the prevalence of pDDIs in ICU patients at BRIMS tertiary care hospital, Bidar.

Methods: This prospective observational study included 30 patients admitted in ICU of BRIMS hospital for >24hrs of either gender, aged >18yrs. The study was conducted for a period of 3 months. Data was collected from the case records of patients on the predesigned proforma. Potential drug-drug interactions were classified based on their severity and the risk of Potential drug-drug interactions was estimated by Lexicomp, inc.version; 3.0.1.drug interact android mobile application.

Results: Out of 35 patients admitted in the ICU, 30 cases were included in the study. The mean age of study population was 56.3years. The study population was exposed to a total of 330 medicines during the hospital stay with an average of 11.7 drugs per patient. The prevalence of pDDI was 93.3% (28) with an average of 9.75 pDDI per patient. According to Lexicomp drug interact android mobile application majority (63%) of pDDI were found to be moderate in their severity, 67% belonged to type C risk.

Conclusions: The study showed higher prevalence of pDDI among ICU patients due to the complexity of the pharmacotherapies administered.


Drug-drug interaction, ICU, Patient safety

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Hartshorn EA. Drug interaction: 1. General considerations. Ann Pharmacother. 2006;40(1):116-8.

Cremades J, Gonzalo M, Arrebola I. Relationship between drug interactions and drug-related negative clinical outcomes. Pharm Pract (Granada). 2009;7(1):34-9.

Moyen E, Camiré E, Stelfox HT. Clinical review: Medication errors in critical care. Critical Care. 2008;12(2):208-14.

Abideen S, Vivekanandan K, Mishra P. Assessment of prevalence of potential drug-drug interactions in medical intensive care unit of a tertiary care hospital in India. Asian Journal of Pharmaceutical and Clinical Research. 2015;8(1):125-30.

Srivstava S. A complete textbook of Medical Pharmacology. 1st ed. Sirmour: Avichal publishing company; 2014.

Franceschi A, Tuccori M, Bocci G, Vannozzi F, Di Paolo A, Barbara C, et al. Drug therapeutic failures in emergency department patients. A university hospital experience. Pharmacol Res. 2004;49:85-91.

Johnell K, Klarin I. The relationship between number of drugs and potential drugdruginteractions in the elderly:A study of over 600,000 elderly patients from the Swedish Prescribed Drug Register. Drug Saf. 2007;30:911-8.

Pea F, Furlanut M. Pharmacokinetic aspects of treating infections in the intensive care unit. Focus on drug interaction Clin. Pharmacokinet. 2001;v.40,11:833-68.

Zagli G, Tarantini F, Bonizzoli M, Di Filippo A, Peris A, De Gaudio AR, et al. Altered pharmacology in the intensive care unit patient. Fundam Clin Pharmacol. 2008;22:493-501.

Kumar MA, Nizar A, Shailaja K, Jayasutha J, Ramasamy C. A study on prescribing pattern and potential drug-drug interactions in type 2 diabetes mellitus (inpatients) in a tertiary care teaching hospital. Der Pharmacia Lettre. 2011;3(4):13-9.

Ahmadizar F, Soleymani F, Abdollahi M. Study of drug interactions in prescriptions of general practitioners and specialists in Iran 2007-2009. Iran J Pharm Res. 2011;10(4):921-31.

Nabovati E, Arki HV, Taherzadeh Z, Hasibian MR, Hanna AA, Eslami S, et al. Drug-drug interactions in inpatient and outpatient settings in Iran: a systematic review of the literature. Daru. 2014;22(1):52.

Gupta M, Chincholkar A, Wagh R, Maheshwari N, Siddiqui W. A study of potential drug-drug interactions among critically ill patients at a tertiary care hospital. International Journal of Basic and Clinical Pharmacology. 2016;:1281-1285.

Lima R, Cassiani S. Potential drug interactions in intensive care patients at a teaching hospital. Revista Latino-Americana de Enfermagem. 2009;17(2):222-7.

Bleich GW, Bleich A, Chiamulera P, Sanches AC, Schneider DS, Teixeira JV, et al. Frequency of potential interactions between drugs in medical prescriptions in a city in southern Brazil. Sao Paulo Med J. 2009;127(4):206-10.

Teixeira JV, Crozatti MT, Santos CA, Lieber NS. Potential drug-drug interactions in prescriptions to patients over 45 years of age in primary care, southern Brazil. Public Lib Sci One. 2012;7(10):1-6.

Nobili A, Pasina L, Tettamanti M, Lucca U, Riva E, Marzona I. Potentially severe drug interactions in elderly outpatients: results of an observational study of an administrative prescription database. J Clinic Pharm Therap. 2009;34(4):377-86.

Oğlu MG, Küçükibrahimoğlu E, Karaalp A, Sarikaya Ö, Demirkapu M, Onat F, et al. Potential drug? drug interactions in a medical intensive care unit of a university hospital. Turkish Journal of Medical Sciences. 2016 Apr 19;46(3):812-9.

Smithburger PL, Kane-Gill SL, Seybert AL. Drug-drug interactions in the medical intensive care unit: an assessment of frequency, severity and the medications involved. Int JPharm Pract. 2012;20:402-8.

Askari M, Eslami S, Louws M, Wierenga PC, Dongelmans DA, Kuiper RA, et al. Frequency and nature of drug-drug interactions in the intensive care unit. Pharmacoepidemiol Drug Saf. 2013;22:430-7.