Evaluation of systemic effect of Pycnocycla spinosa extract in mice using Irwin test

Hydroalcoholic extract of Pycnocycla spinosa has spasmolytic action in vitro. At oral dose of 250 ?g/kg it inhibits castor oil induced diarrhea in mice. If P. spinosa extract has no serious adverse effect, it would be a good alternative medicine for treatment of diarrhoea and abdominal spasm. In this research, overall systemic effect of P. spinosa extract on mice behavior and reaction was investigated. Single acute dose of the extract (500 ?g/kg and 1 mg/kg, i.p.) had negligible effect on animal behavior. However, some changes were seen with dose of 10 mg/kg of the extract. In a group of mice that were treated daily with the extract (10 mg/kg, i.p.) over 3 weeks, a reduction on alertness and marked decrease on defecation was observed on first and second weeks. No significant changes were seen in behavior of the animals that were received the extract in their drinking water over three weeks. Lethal dose causing 50% mortality indicates a large margin of safety.