QUEENSLAND rugby league players have admitted mixing sleeping pills and energy drinks before the third State of Origin match but insist it was an accident.

Maroons players are furious at unsubstantiated claims they deliberately combined Stilnox tablets and Red Bull to get short-term "highs".

The Sydney Daily Telegraph reports a group of players was adversely affected by taking the sleeping medication to help them sleep after partying into the early hours of Saturday morning, July 11.

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They hit Gold Coast nightclubs the previous evening and a source has confirmed some players consumed Red Bull at various bars and clubs.

The players who took Stilnox did so when they got back to their five-star resort early on Saturday, a scheduled day off.

"Yes, some players drank Red Bull and yes, some players took Stilnox," the source said.

"But to say they deliberately mixed them to simulate drugs is way off the mark.

"The players are upset they've been linked to contrived drug use.

"It's a very serious allegation. Stilnox is a prescription drug (and) it's legal. The players who took it did so to help them sleep after getting back to their rooms.

"It did knock a couple of them around after they woke up because they'd been out the night before.

"But there's no way any set out to deliberately do that to themselves. It had an adverse side-effect."

Originally published as Origin drug mix 'accidental'