Frederiksen was one of the stars of the British team in Beijing
Paralympic swimming champion Heather Frederiksen has been given a six-month ban by the International Paralympic Committee for failing a drug test.
The 24-year-old from Wigan tested postive for a raised level of Salbutamol at last October's IPC European Championships in Iceland.
The levels found were higher than those permitted for medical reasons.
The ban was backdated to 23 October meaning Frederiksen, who won five European gold medals, can now compete.
She will lose the gold she won in the S8 100m freestyle as well as silver from the SM8 200m individual medley and bronze from the S9 100m backstroke.
A former talented open-water swimmer, Frederiksen suffered an accident five years ago that left her with reduced mobility down the right side of her body and she was told she would never swim again.
She left the sport but then decided she had some unfinished business to attend to and returned in 2006, working hard to be one of the stars of the British team at the Beijing Paralympics, winning a gold, two silvers and a bronze.
British Swimming chief executive David Sparkes said that the association would continue to support Frederiksen with her training and return to competition.
It is not yet clear when Frederiksen will return to action but she was not named in the British team for the IPC World Championships in Holland in August.
"This was a case where the panel exercised its discretion to impose a far lower period of suspension than the normal length of two years due to the circumstances involved," said Sparkes.
"During the hearing, the athlete produced corroborating evidence, to the comfortable satisfaction of the panel, that she did not intend to enhance performance and the judgement reflects this fact."
In a statement, ParalympicsGB confirmed that it does not have a bye-law in relation to anti-doping that prevents athletes with a doping violation competing at future Paralympic Games.
Therefore Frederiksen would be eligible for selection for London 2012.