Many people use both cigarettes and e-cigarettes (dual use) and want to quit both. However, little is known about the best way to support individuals who want to quit dual use. This study will test different doses of nicotine replacement therapy (patches and lozenges), a medication typically used for quitting smoking, to see which dose is best for people using both cigarettes and e-cigarettes. This study will also see if quitting cigarettes and e-cigarettes can lead to changes in health that might prevent cancer.

Tobacco-free oral nicotine pouches (such as Zyn brand) are a less harmful alternative to combustible tobacco (cigarette/cigarillo/little cigar) smoking. Pouches, however, contain nicotine, and addictive substance that is not risk-free. The present study is evaluating how well nicotine pouches, at different nicotine levels, help people switch away from smoking combustible tobacco. People who smoke will be asked to answer questions about their tobacco product use and provide breath samples and cheek swab samples at an in-person visit to MUSC Charleston. Participants will then be provided with a 28-day supply of nicotine pouches, and will be asked to switch from smoking to pouches over the course of 4 weeks. Finally, participants will complete a final visit at MUSC, and will answer more questions about their tobacco use 1-month later.

While cigarette smoking is detrimental to health and a known risk factor for cancer, e-cigarettes are thought to be less harmful but not entirely risk-free, and less is known about e-cigarette use and changes to health. The purpose of the present study is to evaluate changes in health that may occur when people stop using e-cigarettes. Participants who use e-cigarettes (and who never smoked, smoked in the past, or currently smoke) will be recruited to participate in a laboratory session followed by a week of abstaining from any nicotine use. Throughout the study, participants will provide biological samples for analysis of DNA damage, immune functioning, inflammation, and respiratory functioning at the MUSC Charleston campus. Results will provide insight into the health benefits of quitting vaping.