ORIGINAL ARTICLES Analgesic Effects of a Standardized Bioflavonoid Composition from Scutellaria baicalensis and Acacia catechu

ABSTRACT. Anti-inflammatory properties of both baicalin and catechins have been widely reported. However, the reports of analgesic effects of baicalin and catechins are limited. Three commonly used pain-related animal models were employed to evaluate the analgesic activity ofUP446, a standardized bioflavonoid composition of baicalin and catechins. Carrageenan-induced paw edema, formalin test, and abdominal constriction assays were used to evaluate antinociceptive activity of 150 mg/kg or 100 mg/kg oral doses ofUP446. Ibuprofenwas used as a reference compound in each test. Pretreatment of carrageenan-induced hyperalgesic animals with UP446 at 150 mg/kg oral dosage re-duced the hypersensitivity of pain by 39.5%. Similarly, a single dose of UP446, given orally at 100 mg/kg, exhibited 58 % and 71.9 % inhibition in pain sensitivity compared to vehicle-treated control in writhing and formalin tests, respectively. These findings sug-gest that the standardized anti-inflammatory bioflavonoid composition, UP446, could also be employed to inhibit nociception