Mueller, who is the mother of Sheen's twin sons, Max and Bob, was allegedly rushed to hospital after she was found unresponsive by an assistant at her home in Tarzana, California.
But her spokesman Steve Honig, who until recently represented another embattled star, Lindsay Lohan, insists the drama has been blown out of proportion.
He tells WENN, "An assistant thought Brooke was non-responsive while she was napping and hastily called an ambulance.
"As a precaution, Brooke was brought to a local hospital and discharged after an hour. She was diagnosed with exhaustion and dehydration and is now fine and resting at home. That's it."
Mueller has battled drug addiction in recent years and checked herself in to a drug recovery centre in 2011 in a bid to regain her health. She has been in and out of rehab since, and signed up for a wellness retreat earlier this year (12) to maintain her sobriety.