The former Malcolm in the Middle star was admitted to hospital on Friday (30Nov12) and is now recuperating after the frightening health scare.
Muniz, 26, revealed the news in a post on his Twitter.com page and vowed to start taking better care of himself.
He writes, "I was in the hospital last Friday. I suffered a 'mini stroke', which was not fun at all. Have to start taking care of my body! Getting old!"
The actor, who shot to fame as a youngster opposite Bryan Cranston in the hit TV sitcom, did not reveal any more details about his condition.