Adverse drug reaction profile of patients taking amantadine for traumatic brain injury in a tertiary care hospital

Background: Amantadine is found to be effective for the treatment of complications associated with traumatic brain injury. Drug-related side effects are common with Amantadine especially when combined with other drugs. Comprehensive information about the incidence and severity of these adverse effects is not available. Aim and Objectives: The aim of the study was to analyze the pattern of occurrence of adverse drug reactions (ADRs) in patients receiving Amantadine for traumatic brain injury in a tertiary care hospital. We also assessed the causality, severity, and preventability of ADRs. Materials and Methods: This prospective and cohort study was conducted among patients taking Amantadine for a continuous period of 1 month for traumatic brain injury in neurosurgery department between June 2020 and December 2020. Tools used were ADR Reporting form of National Pharmacovigilance Centre, WHO causality scale, Hartwig and Siegel scale, and Schumock and Thornton scale. Descriptive statistics were used and the values were expressed in numbers and percentages. Results: ADRs were experienced in 55 patients (36.7%) out of 150 patients and all the patients were on combination therapy. ADR was present more in male patients (63.6%) compared to females (36.4%). The most common ADRs were headache, ankle edema, and dry mouth. Majority of ADRs belonged to the possible category according to the WHO causality assessment scale. Majority of the ADRs (61.9%) were mild level 1 according to severity scale. All the ADRs came under the definitely or probably preventable category. Conclusion: ADRs with Amantadine are common but mild and preventable.