Recent studies suggest that there is a direct link between Attention Deficit Hyperactivity Disorder (ADHD), particularly in young subjects, and nicotine consumption. Nicotine is technically a stimulant that reduces the effects of ADHD, so when teens with ADHD begin smoking, it becomes exponentially harder for them to quit due to the benefits it offers them.
Currently, several large drug companies are working to separate the addictive component of the nicotine molecule from the desirable component . The problem they face is that the beneficial aspect and the addictive aspect are highly intertwined. The hope is that in the near future scientists will be able to isolate the non-addictive molecule and create a safe nicotine treatment for ADHD that eliminates the harmful carcinogens.
Sources:
Cocores JA. Transdermal nicotine in ADHD with depression and anxiety. Prim Care Companion J Clin Psychiatry. 2008;10(3):253-4. doi: 10.4088/pcc.v10n0312f. PMID: 18615164; PMCID: PMC2446482.
Jean-G. Gehricke, Carol K. Whalen, Larry D. Jamner, Tim L. Wigal, Kenneth Steinhoff, The Reinforcing Effects of Nicotine and Stimulant Medication in the Everyday Lives of Smokers with ADHD: A Preliminary Examination, Nicotine & Tobacco Research, Volume 8, Issue 1, February 2006, Pages 37–47, https://doi.org/10.1080/14622200500431619
Schoenfelder EN, Faraone SV, Kollins SH. Stimulant treatment of ADHD and cigarette smoking: a meta-analysis. Pediatrics. 2014 Jun;133(6):1070-80. doi: 10.1542/peds.2014-0179. Epub 2014 May 12. PMID: 24819571; PMCID: PMC4531271.