The sanction, which follows two incidents in the County Championship match between Essex and Worcestershire in early September, applies only to that competition and is suspended until the end of the 2014 season.
It caps a difficult period for the player who moved from Sussex to Essex after being fined by police in August for urinating in public.
Panesar, who did not play in the Ashes Tests and was not considered for the final match against Australia following that incident, had hoped the change of club would prompt a change in fortune.
He was recently recalled to the England squad for the return Ashes Test series in Australia that starts in November.
Image: Monty Panesae
Photograph: Gareth Copley/Getty Images
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