The five-time Olympic dressage gold medallist was given the suspension by the world governing body, the FEI, after her horse Whisper tested positive in May.
The decision rules Werth out of international competition until June 23 but will have ended in time for her to compete at the CDIO Aachen event on July 9-18 which is Germany's qualifying event for the WEG in Lexington, Kentucky, in September.
Sönke Lauterbach, secretary-general of the German Equestrian Federation, said: "For the committee it was decisive that the horse of Mrs Werth was doped and with a product of which the application for medical reasons has dangers for the health of the horse according to the FEI Tribunal.
"We have told to committee that we agree with the team suspension and that's what we are going to do."
September 2009: Five-time Olympic gold medallist suspended for doping but still allowed to compete in London 2012
July 2009: Committee refuse Werth resignation despite drug shadow
June 2009: German gold medallist regrets doping incident