The Potential Analgesic Activity of Methanolic Leaf Extract of Carmona retusa (Vahl) Masam (Boraginaceae)

Carmona retusa (Tsaang Gubat), a traditional medicinal plant in the Philippines, has been reported in preliminary studies to exhibit analgesic properties. However, limited scientific validation exists for its use in acute pain management. The study demonstrated that the methanolic leaf extract of Carmona retusa produces a dose-dependent analgesic effect in mice using the acetic acid-induced writhing test. The highest dose (5000 mg/kg) showed the strongest response, with a mean writhing count of 0.2 ± 0.4 comparable to the positive control (15.6 ± 8.55) and significantly lower than the negative control (41.4 ± 6.92). The middle dose (3750 mg/kg) showed strong analgesic activity (3 ± 3.79), while the lowest dose (2500 mg/kg) produced a more variable effect (21.2 ± 15.78). Statistical analysis confirmed significant differences between groups, indicating that analgesic activity increases with dose. These findings scientifically validate the plant’s traditional use for pain relief, especially at higher concentrations of the extract.