Arnica, derived from the Arnica montana plant, is believed to have anti-inflammatory and analgesic properties that may help mitigate the intense pain associated with cluster headaches. Its potential mechanism involves inhibiting nuclear factor-κB and reducing pro-inflammatory cytokines, which could help modulate the neurogenic inflammation and vascular changes characteristic of cluster headache pathophysiology. However, scientific evidence specifically supporting its efficacy for cluster headaches is limited, and more rigorous clinical research is needed to definitively establish its therapeutic role.