Typically, supplements become prescription-only when they exceed a given dose. Much like ibuprofen: you can get that OTC, but there are prescription-only ibuprofen pills that are identical except for dosage. The prescription is required simply because the dosage is at a level that should have medical supervision.

I don't know if this is the case with prescription folic acid, or if there's actually something else different about them, but I suspect it's just a dosage thing.

I did some research out of curiosity, and this medication is not the same as a high-dose folic acid supplement that many people are familiar with.

I can't find the connection between this medication and better outcomes for patients with autism. Even the press release today seems to focus on autism-like symptoms when diagnosed with CFD, not autism. I wonder if this is smoke and mirrors to distract from all the scandals and failures of this administration?

https://news.ycombinator.com/item?id=45348963#45349230