Antihyperalgesic and antiallodynic effects of Salvia rosmarinus Spenn. extracts and some of their bioactive metabolites in a murine fibromyalgia pain model.

Fibromyalgia (FM) is a chronic nociplastic pain syndrome characterized by widespread pain, allodynia, and hyperalgesia. Current pharmacological treatments have limited efficacy and may cause adverse effects. Salvia rosmarinus (rosemary) is a medicinal plant traditionally used to relieve different types of pain and other conditions, as reported in preclinical and clinical studies. However, its potential efficacy in relieving FM pain has not been fully characterized. To evaluate the antiallodynic and antihyperalgesic effects of extracts with different polarities obtained from the aerial parts of S. rosmarinus, as well as some of its bioactive metabolites, in male and female Wistar rats in the reserpine-induced FM model. Essential oil and hexane extracts were prepared as non-polar extracts, whereas ethanolic and aqueous extracts were used as polar extracts of S. rosmarinus aerial parts at 10-300 mg/kg, i.p., and evaluated for antihyperalgesic and tactile and thermal antiallodynia activities in reserpine-induced fibromyalgia in rats; gabapentin (30 mg/kg, i.p.) was used as the reference drug. Representative bioactive metabolites of each extract were also assessed. All extracts produced significant antiallodynic and antihyperalgesic effects, with the ethanolic extract showing the greatest activity. The metabolites hesperidin, caffeic acid, and limonene were partially responsible for these effects. These results support the potential of S. rosmarinus and its metabolites as therapeutic alternatives for relieving nociplastic pain associated with FM.