Phytochemical Screening and Antipyretic Activity of Aqueous Stem Bark Extract of Vitex doniana in Wistar Rats at a North Central Nigerian Research Facility

Vitex doniana, known locally as black plum or dinya among Hausa-speaking communities in North Central Nigeria, is widely used in traditional medicine for the management of fever, malaria, and pain. Despite its popular use in Niger and Kogi States, rigorous pharmacological investigation of its antipyretic activity using standardised experimental models is limited. This study conducted phytochemical screening and evaluated the antipyretic activity of aqueous stem bark extract of V. doniana collected from Minna, Niger State, in brewer's yeast-induced pyrexia in Wistar rats. Phytochemical analysis was performed by standard qualitative tests for alkaloids, flavonoids, tannins, saponins, and cardiac glycosides. Pyrexia was induced by subcutaneous injection of 20% brewer's yeast suspension, and treatment groups received the extract at 100, 200, or 400 mg/kg orally, with paracetamol at 100 mg/kg as the reference drug. Rectal temperature was recorded at hourly intervals for six hours post-treatment. The extract contained flavonoids, tannins, alkaloids, and saponins. All three doses significantly reduced elevated rectal temperature compared to vehicle control from the second hour post-administration. The 400 mg/kg dose produced temperature reduction comparable to paracetamol at three hours. The presence of flavonoids is consistent with the observed antipyretic activity through prostaglandin synthesis inhibition. These findings provide pharmacological support for the traditional use of V. doniana in fever management in North Central Nigeria. Keywords: Vitex doniana, antipyretic, phytochemistry, brewer's yeast pyrexia, Niger State.