Arnica montana is one of the most extensively researched botanicals in European phytotherapy — a daisy-family perennial native to subalpine meadows across central Europe and Siberia whose flower heads contain sesquiterpene lactones (principally helenalin and dihydrohelenalin derivatives), flavonoids, and thymol derivatives that collectively underpin its anti-inflammatory and analgesic reputation. Steam distillation of the flowers produces an oil that is both rare and costly; most commercial arnica preparations are lipophilic infused oils or standardised tinctures, but the essential oil captures the volatile fraction of this well-documented chemistry. A systematic review of clinical trials concluded that Arnica montana is more effective than placebo for post-traumatic and postoperative pain, oedema, and ecchymosis — placing it among the few botanical agents with a credible clinical evidence base in surgical recovery contexts, with sesquiterpene lactone-mediated inhibition of NF-κB activation and COX-2 and 5-lipoxygenase enzymes proposed as the primary anti-inflammatory mechanisms.^[1]