PATTERN & PREDICTORS OF DRUG-DRUG INTERACTIONS AMONG THE PATIENTS ADMITTED IN NEUROLOGY AT A TERTIARY CARE HOSPITAL – A CROSS-SECTIONAL STUDY

Objective: Drug – drug interactions (DDI) is a permanent risk in patients with complex therapeutic regimens. Drugs commonly prescribed in Neurology contribute for most of the potentially hazardous DDI. The present study was undertaken to identify the DDI and its predictors among the patients admitted in Neurology ward. Material and Methods: An analytical cross-sectional study was conducted from January – May, 2015 among the patients admitted in Neurology wards. All the patients on at least two drugs were enrolled. Drug data was analyzed for interactions using the standard drug interaction software. Results: Among 110 enrolled patients, 289 hazardous DDIs were identified, of which 261 were potential DDIs (pDDIs). Atorvastatin and Pantoprazole (14%), Aspirin and Low Molecular Weight Heparin (13%), and Atorvastatin and Clopidogrel (13%) were the most commonly interacting pairs. Commonly encountered antiepileptic pairs that led to pDDIs were Phenytoin and lorazepam (7%) and clobazam and levetiracetam (7%). Majority of interactions were of moderate (72%), followed by major (20%) severity. 69% of DDIs required therapeutic monitoring and 19% required therapeutic modification. Number of prescribed drugs, length of hospital stay, co-morbid conditions and number of anti-epileptic drugs prescribed were identified as the predictors for the development of DDIs [p < 0.05]. Conclusions: 46.3% of the patients admitted in Neurology wards were prescribed with drugs that could lead to DDIs. Majority of the DDIs were moderate in severity and required therapeutic monitoring. Hence, intense monitoring programme needs to be initiated in every hospital for early detection and prevention of DDIs.