Strangely, yes. I can't find a good source for you at present but I've known people who self-medicated this way and it seemed to work for them.

But GP probably meant nicotine.

TBH I’ve smoked weed everyday all day long for over 20 years. Maybe that’s how I’ve gotten by but I’m wondering if there is a better and healthier alternative.

Yes I am serious and I meant nicotine. Many ADHD people are already addicts usually the worst form of it: cigarettes. It is a nootropic with a big health tradeoff. So don't consider yourself unmedicated if you are a user.

In my case, cigars help me a lot, much more than dopamine stimulants. I think acetylcholine stimulation should be studied more by the pharma.