Abstract: A simple and rapid method using mice for testing antitussive agents is reported. Mice were put into a small glass chamber, one by one, and exposed to atomized ammonium hydroxide for various lengths of time. By using a sequential test design the time of exposure that makes 50 per cent of mice cough(EDT₅₀) could be easily obtained. Agents which significantly prolong EDT₅₀ are considered to be potential antitussives.This method has been shown to be suitable to demonstrate the activity and potency of known antitussive drugs such as codeine, toclas, etc. Compounds, including germacrone, 4-phenyl-hutanone-2 and hyperin which were found in our laboratory to exhibit satisfactory antitussive activity by this method, were also shown to be effective in controling cough clinically.