Antitussive properties of the root extract and fractions of Acanthospermum hispidum (L)

Acanthospermum hispidum (Asteraceae) is plant widely used in South Eastern Nigeria to treat cough. This study investigated the antitussive properties of the root extract and fractions of A. hispidum. The antitussive effects of oral administration of 400 and 800 mg/kg of A. hispidum root methanol extract (ME), hexane (HF), ethyl acetate (EF) and methanol fractions (MF) were evaluated using sulphur (iv) oxide and ammonia induced cough models in mice. The extract and fractions were subjected to acute toxicity test, phytochemical analysis and HPLC finger printing. The extract and fractions of A. hispidum exhibited strong and significant antitussive effects in both cough models. The MF and EF exhibited significant (p< 0.01) antitussive effect when compared to the control. The inhibition of ammonia induced cough (86.6 %) was greater than sulphur (iv) oxide induced cough (47.2 %). An oral LD50 value >5000 mg/kg in mice was established for the extract. Phytochemical analysis revealed the presence of saponins and flavonoids which may be responsible for its antitussive effects. Results revealed the antitussive property of A. hispidum and root which correlate to its ethnomedicinal use to relieve cough.