Efficacy and outcomes of pharmacological treatments for headaches after traumatic brain injury: A systematic review.

BackgroundHeadache following traumatic brain injury (TBI) is a common, yet disabling, disorder with diverse mechanisms and treatment needs that remain poorly defined. Pharmacological regimens are the primary source of remedies for individuals with post-traumatic headaches (PTH). The main objective of this review is to describe the efficacy of pharmacological medications for the treatment of PTH with a specific focus on the effect of these medications on headache characteristics and headache-related quality of life (QoL).MethodsThis systematic review (CRD42024537719) followed PRISMA and SWiM guidelines. PubMed, CINAHL, Scopus, PsycINFO and the Cochrane Library were searched in April 2024 for peer-reviewed articles published in English between 2009 and 2024. Eligible studies included randomized controlled trials, controlled cohort studies, and systematic reviews or meta-analyses evaluating pharmacological treatments for PTH in adults. Studies were excluded if they did not assess outcomes related to PTH pain, only included pediatric populations, used animal models, investigated only non-pharmacological interventions, were case reports, narrative reviews, editorials or conference abstracts, or did not involve human participants with TBI-related headache. Risk of bias was assessed using RoB-2 for Randomized controlled trials (RCTs) and ROBINS-I for the non-randomized studies of the effects of interventions.ResultsSixteen studies were included in the final review, comprising retrospective observational (n = 7), non-randomized prospective (n = 4) and randomized controlled trials (n = 5). Most studies reported some improvements in headache frequency and intensity following pharmacological treatment, although findings for headache-related QoL were inconsistent. Erenumab showed potential benefits for persistent PTH in small, uncontrolled studies of civilian samples. However, findings on its impact on headache-related QoL should be interpreted with caution, given the high discontinuation rate observed. Prazosin demonstrated similar benefits in military populations, with minimal side effects. In the acute care setting, metoclopramide, co-administered with diphenhydramine to minimize side effects, was associated with short-term relief of headache symptoms. Of the RCTs, only two had a low risk of bias, of which only one specifically focused on PTH.ConclusionsPharmacological treatments for PTH may provide improvements in headache frequency and intensity; however, evidence for their efficacy is limited and inconsistent. Given the limited high-quality evidence overall, no specific clinical recommendations can be made at this time. Future research should prioritize rigorous, controlled studies, particularly comparative effectiveness trials, and explore holistic, personalized approaches that incorporate treatment of psychiatric comorbidities and consider patient context.