Another similar problem because of this I have seen first and second hand was the removal of otc asthma medication that contains ephedrine hcl and/or ephedrine sulfate. Friends and family members of mine with asthma used to have bottles of it, carry it all the time and treated it like it was an aspirin for a "bad day to have asthma".
Nowadays you have to show ID, get put on a list, and can only buy so much in a strict time period.

While the removal of this didn't stop meth use, it definitely stopped the accessibility of an effective and reliable solution for those who have asthma.