Chris Gascoyne, who plays the alcoholic, has been spotted filming scenes which see Peter desperately clutching a bottle of vodka outside an off-licence.
The episode in question is expected to air later this year as Peter's relationship with wife Leanne hits another rocky patch.
A Coronation Street source told The Sun: "When things go wrong at home, he can't help turning to drink again."
Peter has endured a turbulent few months with Leanne as his close connection with Carla Connor (Alison King) has often come between them. They also came close to splitting in February in the fall-out of Leanne's affair with Nick Tilsley (Ben Price).
Jane Danson, who plays Leanne, recently said that her character is "prepared to fight for her husband" amid their current struggles.
Coronation Street continues on Thursday at 8.30pm on ITV1.
> Coronation Street Carla plot has high drama ahead, says Alison King
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