Patrick Schwarzenegger is denying speculation that he did drugs at the Coachella Valley Music and Arts Festival in Indio, California, over the weekend.

After the 22-year-old son of Arnold Schwarzenegger and Maria Shriver was caught on camera popping a mystery pill at the fest, his rep tells ET that it was "Party Smart," an herbal supplement designed to prevent hangovers when drinking.

"He doesn't take drugs," the rep added.

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Patrick stayed relatively quiet on social media through the weekend, sharing only one pic on Instagram of himself with celebrity chef Guy Fieri. "Had to ask for a photo," he captioned the shot, posing with his tongue out and a drink in his hand.

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Last summer, with Patrick making his feature film debut in Midnight Sun, his famous dad revealed the sage advice he offered about making it in Hollywood.

"This whole idea of him going to USC to study business and economics is because he wanted to be an entrepreneur," Arnold told ET's Ashlan Cousteau in July 2015. "He figured out that I have always taken care of my own money. I've never had a business manager and I'm the only one in entertainment that never lost any money. He wants to make sure he's falling in the same category of 'let's worry about how much money we make and also how much money we keep.' That's very smart."

See the interview in the player below.