hypericum and Fever

To assess the usefulness of rectal temperature responses in Australian bred Merino sheep, following the oral administration of Hypericum perforatum (St John's wort), as an early indicator of Hypericum intolerance.. Thirty-three Merino ewes were divided into three groups of 11. Each group was dosed with finely ground, dried, flowering growth stage H perforatum plant material at either 5.7, 4.0, or 2.85 g dry plant per kg live weight. This corresponded to 5.3, 3.7 and 2.65 mg hypericin per kg live weight, respectively.. The sheep were dosed with a plant slurry by stomach tube and then exposed to bright sunlight for up to 5 h per day over successive days. Their clinical responses were observed and rectal temperature measured.. Ingestion of H perforatum followed by exposure to bright sunlight frequently resulted in clinical signs attributable to skin irritation and central nervous effects, including an inappropriate increase in body temperature. A decrease in H perforatum ingestion from 5.7 to 2.85 g dry plant per kg live weight and a corresponding decrease in hypericin ingestion from 5.3 to 2.65 mg per kg live weight, was associated with a decrease in the severity of the clinical signs, including the severity of the hyperthermia.. The rectal temperature rise in affected sheep is a reliable indicator of the early development of an adverse clinical effect. There appears to be an absolute requirement for exposure to bright sunlight before any effects of H perforatum will develop. A single dose of H perforatum remains potentially effective for up to 4 days. In the small group of Merino sheep tested a tolerance level for H perforatum, eaten at the flowering stage, of < 1% (plant wet weight) of body weight and a tolerance level for hypericin of < 2.65 mg per kg live weight, were demonstrated.

Topics: Animals; Body Temperature; Female; Fever; Hypericum; Plant Poisoning; Plants, Medicinal; Sheep; Sheep Diseases; Sunlight

The present therapeutic agents for the treatment of pain, inflammation and pyrexia are not very effective and accompanied by various side effects. Therefore, new effective agents are the most wanted. The present study investigates the anti-nociceptive, anti-inflammatory and antipyretic activities of crude methanol extract of Hypericum oblongifolium.. In vivo acetic acid induced writhing and hot plate tests were used for antinociceptive effects at 100, 200 and 300 mg/kg i.p. The anti-inflammatory and antipyretic potential of methanol extract were tested in carrageenan induced paw edema in mice and yeast induced hyperthermia respectively.. The extract doses of 100, 200 and 300 mg/kg i.p. revealed significant inhibitory effect (P < 0.001) in acetic acid induced writhing test. Pretreatment of extract at doses of 100, 200 and 300 mg/kg i.p. produced significant anti-inflammatory effect (P < 0.001) in the carrageenan induced paw edema. The methanol extract also showed significant antipyretic effect in yeast induced hyperthermia in mice during various assessment times.. The methanol extract of H. oblongifolium showed significant anti-nociceptive, anti-inflammatory and antipyretic effects in various animal models and thus validates the traditional uses of the plant in said conditions.

Topics: Analgesics; Animals; Anti-Inflammatory Agents; Female; Fever; Hypericum; Inflammation; Male; Mice; Mice, Inbred BALB C; Pain; Phytotherapy; Plant Extracts; Plants, Medicinal