There are so many claims of autism being cured in a couple people with different drugs or supplements out there.

They’re always followed by thousands of self-experimenters where nobody can reproduce the result.

The explanation is almost always placebo effect. A parent or doctor is so convinced that they’ve found a cure that they change assume it worked, change their behavior toward the autistic person, and believe that a dramatic change has occurred.

This is also why the placebo arm of every autism study also shows improvement.