Kolo Touré will discover on Thursday whether he is to face an extended ban for failing a drugs test, with the Manchester City player due to appear before a Football Association disciplinary hearing to explain why he tested positive for a specified substance in February.

Touré's legal team are expected to argue that the Ivory Coast international did not know he was breaking rules when he apparently took his wife's dieting pills and that he was concerned about his weight because of the intense competition for places at Eastlands.

However, the 30-year-old is braced for a substantial ban, quite possibly into next year, if the case is proven against him, after being the first Premier League footballer since Adrian Mutu to be charged with taking an illegal substance. The FA can operate a range a punishments up to a two-year suspension, although whatever it decides for the former Arsenal player will be backdated to the date when he was suspended by his club three months ago.

As a gauge of what Touré might expect, Rio Ferdinand of Manchester United was banned for eight months and fined £50,000 in 2003 after missing a drugs test. However, Paddy Kenny is the clearest example of how taking the wrong over-the-counter product can have serious ramifications, receiving a nine-month ban in 2009 when he was a Sheffield United player.

Kenny, now at Queens Park Rangers, admitted having ephedrine in his system but maintained that he had simply been taking a cough cure to combat a chest infection. More recently, the Hamilton midfielder Simon Mensing served a month-long suspension after tested positive for the methylhexaneamine, which was present in a dietary supplement.

Touré has already delivered a full report to the FA about the circumstances surrounding the alleged offence. However, the game's governing body will also be acutely aware that footballers are specifically warned against taking medicines without advice because of the possibility they may be infringing the rules. If Touré is found guilty and punished with a ban that goes into next season, he will not even be allowed to train with his City team-mates.

Touré, who joined City for £14m in 2009, will argue that he has already been heavily punished after missing the culmination to a season that finished with City qualifying for the Champions League for the first time as well as winning the FA Cup, their first trophy since 1976.

His absence from the team is already threatening to have repercussions on his career, with the City manager, Roberto Mancini, in Abu Dhabi on Wednesday for talks with the club's owners about their spending plans for the summer. Mancini is keen to bring in another centre-half to play alongside the club's player of the year, Vincent Kompany, and a ban of nine months or longer for Touré could have dire consequences for his future at the club.