Gabapentin and Tricyclics in the Treatment of Post-Concussive Headache, a Retrospective Cohort Study.

OBJECTIVE: To examine the association of commonly prescribed post-concussive medications, namely gabapentin and tricyclic antidepressants (TCAs), with symptom reduction after concussion.

BACKGROUND: Concussion is a common diagnosis in modern medicine. Many providers use medication to target the residual symptoms of a concussion, with little evidence supporting their efficacy.

DESIGN: Retrospective study with longitudinal analysis using mixed-effects and piecewise regression analyses of 277 patients presenting to an academic sports medicine clinic, all of whom were clinically diagnosed with a concussion. Main outcomes were patient-reported headache score (quantitative variable; 0-6) and combined symptom score (quantitative variable; 0-132) from the Post-Concussion Symptom Scale (PCSS).

METHODS: Patients self-reported their symptom scores on the PCSS at the time of each clinic visit. Gabapentin or TCAs were prescribed to some patients during their follow-ups for headache treatment, based on physician judgment. Patients were classified into 3 groups: (1) no medication; (2) gabapentin; or (3) TCAs. Follow-up data were evaluated over 1 year. A mixed-effects and piecewise regression analysis were performed to assess long- and short-term effects of medication status.

RESULTS: The mixed-effects analysis showed a significant decrease in both headache and symptom scores over time in each medication group and in those not receiving medication (P ≤ .014 for all scenarios, B = -0.005 and -0.08, respectively). Although patients in the 2 medication groups showed significantly higher headache and symptom scores (P < .001), neither medication had a significant effect on longitudinal improvements in the outcome scores. The piecewise regression, however, showed short-term improvements with gabapentin (1.3 points, P = .004) and more sustained improvements with TCAs (3.5 points, P = .006).

CONCLUSIONS: Patients recover from a concussion with time, regardless of medication. Gabapentin and TCAs appear to have immediate effects on improving symptom burden, but long-term outcomes show similar improvement compared to those who are not prescribed medication. More rigorous prospective studies are required to better elucidate their efficacy.