One of the downsides of adhd is, if left untreated, it can lead to substance abuse. One of the upsides is it’s easier to “forget” that you’re addicted to something. I once forget to drink caffeine for a few weeks. Just slipped my mind. I still had the withdrawal symptoms. Headaches, low energy etc., but my brain would not connect the withdrawal to the substance, because from my perspective caffeine did not exist. It was a weird experience.
I’ve done that a few times. I also quit smoking that way when I ran out of cigs, didn’t buy more right away, then forgot to ever buy more. I started back up months later, switched to vaping, then forgot about that too when I moved the vape from it’s designated spot to an area of the house I don’t frequent.