Effect of COVID-19 Vaccination on Managing Chronic Migraine with Botulinum Toxin: A Case Series

Introduction: Although post-vaccination headaches have been reported following COVID-19 (Coronavirus Disease 2019) immunization, the specific effect of such vaccination on chronic migraine (CM) management utilizing botulinum toxin remains unexplored. This case series highlights the experiences of five CM patients who, despite initially responding well to abobotulinum toxin type A (BTX-A) treatment, experienced increased headache frequency post-COVID-19 vaccination. These findings suggest the potential implications of COVID-19 vaccination on the efficacy of CM management strategies. Case Presentation: This case series highlights five female patients diagnosed with CM, aged 31 - 50 years, with varying past medical histories and concurrent medications, whose number of headache days increased following COVID-19 vaccination (with either Sinopharm or AstraZeneca). All patients were undergoing an ongoing clinical trial at Sina Hospital in Tehran, Iran, receiving BTX-A treatment according to a standard protocol. Routine neurological examinations and brain MRIs (magnetic resonance imaging) were performed, and they were asked to complete monthly headache diaries detailing the frequency and intensity of headaches and abortive medications used. Conclusions: Based on the observed outcomes, the authors hypothesize that COVID-19 vaccination within the initial month of botulinum toxin administration could attenuate its efficacy in managing CM. Patients should be made aware of this possibility. Consequently, it is recommended that physicians might consider rescheduling the administration of BTX-A for CM management based on their clinical judgment.