Safety profile of Calea uniflora Less. in preclinical studies

Calea uniflora Less known popularly as Arnica in Brazil, is a native plant from Brazil, popular used by coastal populations from south of Santa Catarina. The purpose of this study was to verify the safety profile in of hydroalcoholic extract of C. uniflora inflorescences. The hydroalcoholic extract of C. uniflora inflorescences was evaluated for its acute and sub-acute toxicity. Acute topical toxicity was performed using the methodology of guideline 402 from OECD. Acute oral toxicity was performed using the methodology of guideline 423 from OECD and sub-acute toxicity was performed using the methodology adapted of guideline 407 from OECD. The single dose for oral or topical administration of C. uniflora showed DL50 > 5000 mg/kg b.w. The sub-acute treatment induced animal death in groups which was administered extract in the doses 100, 250, 500 and 1000 mg/kg. The main signs of toxicity observed were respiratory difficulty, increase in lung weigh, lung damage and muscular relation.The topical or oral administration of C. uniflora extract in short period did not caused toxicological effects in animals, however, when administered for a longer period and in concentrations of 250, 500 and 1000 mg/kg (oral.) caused lung damage and even the death of the animal.