The 51-year-old is suspected of having bought the drugs in a night club in the western German state of North Rhine-Westphalia.
"The charges date from 2007. It is not my client's fault that they are only being dealt with now," his lawyer Ina Klimpke told Bild daily. "In my opinion he is in such a bad physical and psychological state that it will be difficult for him to endure the trial."
"I was sucked in to it," said Immel, who is nevertheless determined to face the charges before the Dortmund court. "Certain people have now pressed charges out of revenge."
Immel made 19 appearances for Germany between 1980 and 1988 during a long and colourful career, which also featured drug use, numerous affairs and fast cars. He was in the German European Championship winning squad in 1980, though he didn't play, and in the 1986 World Cup in Mexico, when Germany finished runners-up.
He played 534 games in the German Bundesliga in a domestic career that stretched from 1978 to 1995, winning the championship in 1992 with Stuttgart. Oliver Kahn is the only goalkeeper to have played more Bundesliga games than Immel, and only two other German goalies have beaten his 147 clean sheets.
In an interview with the Süddeutsche Zeitung in 2008, he referred to George Best's famous quotation "I spent a lot of money on booze, birds and fast cars. The rest I just squandered."
"That's only partly true for me," Immel said. "Ok, I totalled a few cars and spent a lot of money on my Porsches and Mercedes, but I spent lot more on good-looking women, to be honest."
Immel retired as a player in 1997, when he left Manchester City, and despite three jobs as a goalkeeping coach, he ran up crippling six-figure debts, and was left to live on €985 a month. He appeared on Germany's version of "I'm A Celebrity..." TV show in 2008 to fund a hip operation, Bild newspaper reported.
Cocaine abuse has led to previous encounters with the law. In 2009, police searched his flat in front of his 21-year-old daughter. "That was bad," Immel commented at the time.