Newmarket trainer Gerard Butler has been charged by the British Horseracing Authority over his use of the drug Sungate, which contains a banned anabolic ster-oid.

Butler, who trained at Churn Stables at Blewbury, near Didcot, for nine years up to May 2008, admitted to being subject to a BHA investigation concerning the joint treatment, which was developed by an Italian company and contains stanozolol.

While it is legal to use the drug in Britain when it is imported under licence, the active ingredient is a prohibited substance in racing.

Butler admitted in a newspaper interview that several horses in his stable were treated for joint injuries after receiving assurances from a veterinary practice, and he entered this into his official medical records.

The trainer has been charged with seven breaches of the rules, with the BHA confirming nine of his horses had tested posititve for stanozolol when samples were taken on February 20.

He has been charged with acting in a manner prejudicial to the integrity, proper conduct and/or good reputation of horseracing by administering the steroid.

Butler also faces further charges relating to injecting the horses joints himself, which is contrary to the Rules of racing as he is not a qualified or registered veterinary surgeon.

He is also charged with two counts of failing to keep a record of treatments for several horses.

Butler now faces a BHA disciplinary panel hearing, the date of which is to be fixed.