Abstract
Inflammation, pain, and fever cause discomfort and misery and lower the productivity and quality of life among the victims. The severe effects of synthetic drugs used to treat these conditions necessitate the need for alternative therapeutic agents. Strychnos henningsii is used in folkloric medicine to manage inflammation, pain, and fever, although scientific evidence to validate these claims is lacking. This study aimed to determine the in vivo anti-inflammatory, antinociceptive, and antipyretic potential of the methanol extract of S. henningsii. In the anti-inflammatory, antinociceptive, and antipyretic assays, animals (n = 5) were randomly assigned into six groups: normal control, negative control, diclofenac control, and extract-treated at 25, 50, and 100 mg/kg body weight (bw). Inflammation and pain were induced through injection of 5% formalin (50 μL) in the left hind paw, while pyrexia was induced through intraperitoneal injection of steam-distilled turpentine (20 mL/kg bw). The extract was also subjected to phytochemical screening using gas chromatography-mass spectrometry (GC-MS). The extract at the three doses significantly reduced paw edema, time spent in nociception, and rectal temperature relative to the negative control (p < 0.05), indicating anti-inflammatory, antinociceptive, and antipyretic effects, respectively. In the fourth hour, the extract at 25, 50, and 100 mg/kg bw inhibited paw edema by 4.34 ± 0.15, 6.13 ± 0.29, and 7.43 ± 0.42%, respectively. In the early and late phases, the extract at 100 mg/kg bw inhibited pain by 61.18 ± 0.75 and 66.71 ± 0.93%, respectively. In the 4th hour, the extract at 25, 50, and 100 mg/kg bw inhibited pyrexia by 1.97 ± 0.13, 2.39 ± 0.17, and 2.54 ± 0.17%, respectively. These effects were dose-dependent and were associated with phytochemicals identified using GC-MS analysis, such as terpenes, polyphenols, fatty acids, and salicylates. The study concluded that the extract possesses phytocompounds with anti-inflammatory, antinociceptive, and antipyretic potential and could be an alternative therapeutic agent against pain, inflammation, and pyrexia.