The Rugby Football League’s disciplinary committee have ordered the 27-year-old to appear before them tomorrow after he was alleged to have bitten Catalan Dragons scrum-half Remy Marginet.
The grade E offence is said to have occurred in the last minute of Harlequins' 48-22 defeat in Perpignan on Saturday. Howell could be banned for two months if found guilty.
Biting is ranked alongside gouging and spitting and just below assault of a match official, with suspension ranging from four to eight matches.
Howell was playing his first game for more than two months after recovering from a knee injury.