A pal says the former Full House star really struggled when his mother died last year


After being charged with a DUI, John Stamos was hospitalized for an unknown medical condition. Subscribe now for all the details on the arrest and what his friends are saying – only in PEOPLE.

When John Stamos was pulled over in Beverly Hills and charged with a DUI on Friday, friends of the actor were hopeful this was a one-time mistake. Yet “even though John remains confident and cool, there’s been a change in the past two years,” a pal allows in this week’s issue of PEOPLE.

According to the police, Stamos, 51, who was driving erratically, was taken to Cedars Sinai Medical Center and later released. A spokesman for the police department told PEOPLE that the actor was “having a medical condition” and was not given a field sobriety test.

While Stamos’ career has been going strong – he is set to star in and produce the Netflix Full House spin-off, Fuller House, and is the lead in the new Fox sitcom Grandfathered – friends say he really struggled when his mom, Loretta, died last September. “That was crushing for him,” says a member of his circle. “He did his best to stay strong, but he absolutely fell apart.”

For now, friends of the actor, who was spotted at LAX catching a flight to Toronto on June 14, are hoping for the best. “John has always drunk socially,” adds his pal. “At one point, it was a problem. But this is not that time in his life.”

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For more on Stamos’ DUI charge and his friends’ reactions, pick up this week’s issue of PEOPLE, on newsstands Friday