Warner-Lambert is launching a commercial for Listerine mouthwash featuring comedian and actor Keith Allen. The 1.9m ad, through J Walter Thompson, portrays Allen as a winged tooth fairy who gets frust-rated with the power of Listerine. Listerine’s first commercial for two years begins its three-month run on Monday May 12. It is directed by Trevor Robinson, who worked on the Tango campaign. With the launch of FreshBurst Listerine and the aid of radio advertising, Listerine has become the biggest brand in the mouthwash market. The brand’s market share has risen from 20 per cent to almost 24 per cent by value.