(CBS) As more and more children are diagnosed with autism, there's a growing need for alternative treatments.

And, a mother in California says medical marijuana has resulted in vast improvements in her autistic son, reports "Early Show" National Correspondent Hattie Kauffman.

Mieko Perez tells Kauffman, "Everyone who came to my home was watching me watch Joey die. He was deteriorating hourly."

Joey is severely autistic, Kauffman explains, so uninterested in food he was wasting away. At ten years old, he weighed just 48 pounds. Even bulky Halloween costumes couldn't disguise his frightening look of starvation. He basically only ate, like, peanut butter and jelly sandwiches for four years, Mieko recalls.

But, claims Mieko claims, it all changed with marijuana brownies.

She says not only is Joey eating more, he's communicating. "We're seeing Joey come out!" Mieko exclaims. "He's never made noises. ... We didn't even know he could make noise until the first batch of brownies."

Medical marijuana is often prescribed for cancer and AIDS patients who need to gain weight, Kauffman notes, but a prescription for a child is unusual.

The American Academy of Pediatrics opposes legalization of marijuana, but supports more research.

And, Kauffman stresses, though there's absolutely no evidence marijuana helps with autism symptoms, Mieko insists it has improved her child's life.