Formulation and Acute Toxicity, Anti-Inflammatory, Analgesic Effects of Hard Capsules Containing Dry Extract of Siegesbeckiae Orientalis in Experimental Animals

Abstract

This study aimed to investigate the acute toxicity, analgesic, and anti-inflammatory effects of hard capsules containing dry extract of Siegesbeckia orientalis L. (CKHT) in animal models. Hard capsules were prepared using the volumetric method, with Avicel PH 102 as the diluent excipient and magnesium carbonate as the adsorbent excipient. The acute toxicity of CKHT was assessed on mice at a dose of 2,400 mg/kg body weight. The anti-inflammatory effect was evaluated using a carrageenan-induced paw edema model in rats, while the analgesic effect was tested using an acetic acid-induced writhing model in mice. The results showed that CKHT administered at the doses of 102.2 mg/kg/day, 204.4 mg/kg/day, and 408.8 mg/kg/day had a significant anti-inflammatory effect on the carrageenan-induced rat paw edema model by reducing the paw volume and increasing the percentage of edema inhibition compared to the untreated group (p < 0.001). The dose of CKHT 408.8 mg/kg/day showed anti-inflammatory effects similar to aspirin at the dose level of 200 mg/kg/day (p > 0.05). In the analgesic study, mice treated with CKHT at the doses of 188.7 mg/kg/day, 377.4 mg/kg/day, and 754.8 mg/kg/day had a significant reduction in acetic acid-induced writhing within 30 minutes compared to the untreated group (p < 0.001). Furthermore, CKHT did not show acute toxicity (no LD₅₀) at the dose of 2,400 mg/kg body weight. These results suggested that CKHT exhibited acute analgesic and anti-inflammatory effects in animal models.

Keywords: Dried extract of Siegesbeckia orientalis L.; capsules; anti-inflammatory; analgesic.