Vivid Dreams and Nightmares as an Adverse Effect of Beta-Blockers in the Treatment of Episodic Migraine.

Beta-adrenergic blockers are effective in migraine prevention but can induce neuropsychiatric side effects, including vivid dreams and nightmares. Their lipophilicity allows penetration of the central nervous system, where β1-adrenergic blockade may disrupt REM sleep, alter noradrenergic activity, and suppress melatonin secretion, contributing to emotionally intense dreams. While reported in cardiovascular patients, this adverse effect remains underrecognized in migraine therapy. Adult patients were identified from those seen in the outpatient department of the Clinical Hospital of University of Chile in Santiago between 2022 and 2024. We present three cases of patients with episodic migraine with aura who developed distressing, recurrent nightmares after initiating propranolol, or metoprolol. Symptoms emerged shortly after treatment initiation and resolved upon discontinuation. Nightmare content involved emotionally distressing themes, leading to significant psychological discomfort. Clinicians should be aware of vivid nightmares as a potential adverse effect of lipophilic beta-blockers in migraine prevention. Understanding this may enable patients to tolerate the symptom. If it impacts adherence and/or quality of life, a treatment change will be needed.