An Observational Study on Drug-Drug Interactions in the Critical Care Unit of A Tertiary Care Hospital

• Merit koju

  Karnataka College of Pharmacy, Rajiv Gandhi university of health sciences, Bengaluru, Karnataka, India.

  Author

• Jeeva George

  Karnataka College of Pharmacy, Rajiv Gandhi university of health sciences, Bengaluru, Karnataka, India.

  Author

• Balakeshwa Ramaiah

  Karnataka College of Pharmacy, Rajiv Gandhi university of health sciences, Bengaluru, Karnataka, India.

  Author

• Sachin A.H

  Karnataka College of Pharmacy, Rajiv Gandhi university of health sciences, Bengaluru, Karnataka, India.

  Author

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Background:
Polypharmacy among critically ill patients significantly elevates the risk of drug-drug interactions (DDIs), which can compromise patient safety and clinical outcomes. Understanding the prevalence and impact of these interactions is crucial for enhancing patient safety, optimizing therapeutic efficacy, and minimizing adverse events. Effective DDI management necessitates diligent monitoring, medication reconciliation, and informed clinical decision-making.

Methods:

This study aimed to identify and classify major drug interactions in ICU patients into pharmacodynamic and pharmacokinetic categories, using Lexicomp software for risk assessment. The number of prescribed medications was recorded, and therapeutic outcomes, observed effects, and severity of interactions were analysed to determine the potential for clinically significant DDIs.

 Results:
The study included 93 ICU patients who were prescribed various medications, among which 123 drug interactions were identified. Of these interactions, 15% were classified as major, 69% as moderate, 10% as minor, and 6% as contraindicated. Clopidogrel and heparin were commonly involved as object drugs, while azithromycin and bisoprolol frequently acted as precipitant drugs. Notably, azithromycin and heparin were associated with major interactions. Approximately 28% of interactions had clinically observable effects, with pharmacodynamic interactions being slightly more prevalent. The identified DDIs commonly resulted in adverse outcomes such as toxicity, bleeding, and hypotension. A higher incidence of DDIs was noted in patients over 60 years of age and among female patients.

Conclusion:
Drug-drug interactions are prevalent in critically ill patients, particularly among those who are older and experiencing polypharmacy. Regular medication review and vigilant monitoring are imperative to mitigate risks and improve patient outcomes.

The data supporting the findings of this study are available within the article and its supplementary materials. Additional datasets generated and/or analyzed during the current study are available from the corresponding author upon reasonable request.

1. Merit koju, Karnataka College of Pharmacy, Rajiv Gandhi university of health sciences, Bengaluru, Karnataka, India.

   Department of Pharmacy Practice 

2. Jeeva George, Karnataka College of Pharmacy, Rajiv Gandhi university of health sciences, Bengaluru, Karnataka, India.

   Department of Pharmacy Practice 

3. Balakeshwa Ramaiah, Karnataka College of Pharmacy, Rajiv Gandhi university of health sciences, Bengaluru, Karnataka, India.

   Department of Pharmacy Practice 

4. Sachin A.H, Karnataka College of Pharmacy, Rajiv Gandhi university of health sciences, Bengaluru, Karnataka, India.

   Department of Pharmacy Practice

Copyright (c) 2025 Merit koju, Jeeva George, Balakeshwa Ramaiah, Sachin A.H (Author)

This work is licensed under a Creative Commons Attribution 4.0 International License.