Efficacy of modafinil, methylphenidate, amantadine, and zolpidem in consciousness recovery in intensive care unit patients with traumatic brain injury

OBJECTIVE: Traumatic brain injury (TBI) is the most common cause of death and disability in persons between 15 and 30 years of age. Although various pharmacological agents have been reported to enhance consciousness recovery, few trials have studied these medications in patients with acute TBI. The objective of this study was to determine the effect of modafinil, methylphenidate, amantadine, and zolpidem in improving wakefulness in patients with TBI in an intensive care unit (ICU) setting and to identify any adverse drug reactions. METHODS: Retrospective chart review identified all patients prescribed modafinil, methylphenidate, amantadine, or zolpidem; only patients older than 18 years with TBI in an ICU setting were further analyzed. The electronic medical record was used to retrieve clinical data including patient demographics, mechanism of TBI, drug dosage, treatment duration, Glasgow Coma Scale (GCS) score, length of time to improve GCS score, hospital length of stay, reported adverse drug reactions associated with above medications, and mortality. The primary outcome was the rate of positive response in the clinical neurological exam. Secondary outcomes included change in baseline and final GCS score, time to response, duration of treatment, change in GCS score over time, length of hospital stay, and in-hospital mortality. Descriptive statistics were used to analyze the data. RESULTS: The final analysis included a total of 53 patients. Median ages ranged from 44.0 to 61.5 years; 85% of patients were male. Baseline median GCS score was 8.0 in the amantadine group; 6.5, modafinil; 7.5, methylphenidate; and 7.0, zolpidem. The highest positive response rate was 90% in the amantadine group, followed by modafinil, 77%; methylphenidate, 50%; and zolpidem, 36%. The change in baseline GCS score and median final GCS score for amantadine, modafinil, methylphenidate, and zolpidem was 2.5, 3.0, 1.0, and 0, respectively (P = 0.20). The median time to response in days was 1.5, 1.0, 0.5, and 1.0, respectively. Change in GCS score over time for amantadine, modafinil, methylphenidate, and zolpidem was 0.16, 0.38, 0.12, and 0, respectively. Though rare, the most common adverse events were agitation, hypertension, and posturing. CONCLUSION: It remains to be determined if these medications have a role in reducing ICU and hospital length of stay, length of mechanical ventilation, tracheostomies, and overall medical costs in managing TBI patients. In our study amantadine was associated with the highest overall positive response rate when used as an awakening agent in TBI. Modafinil was associated with the largest change in GCS score over time.