I'd recommend methylphenidate if you havent already, or adderall. i definitely dont trust myself to use nicotine responsively but alterations in genes when it comes to adhd has been observed leading to dysfunction when it comes to your acetylcholinergic, dopaminergic, noradrenergic or glutaminergic system.
if you do decide to use nicotine though, skin patches are the best option as nicotine has half of its effects subsidize by 30 minutes (and skin patches extend its duration). its not generally good to recommend it though due to its addictive nature, especially with that risk being higher when it comes to people with ADHD
