Understanding Oral Nicotine Pouch Use in Healthy Volunteers

The goal of this clinical trial is to understand how using oral nicotine pouches effects the body in healthy volunteers. The main questions it aims to answer are: 1. With multiple use of oral nicotine pouches (ONPs) throughout the day, participants will adjust their intake of nicotine to be similar to or higher than that seen with cigarette smoking or vaping. 2. With multiple use of ONPs throughout the day, participants will experience satisfaction, psychological reward and relief of withdrawal symptoms similar to that seen with cigarette smoking or vaping. Participants will rate ONP use as a satisfactory substitute for cigarette smoking or vaping. 3. Examine the cardiovascular effects (blood pressure and heart rate) of placebo, 3mg and 6mg ONPs, and the participants' usual cigarette or e-cigarette (vape). Participants will: * use 3 different strengths of ONPs (0 mg, 3 mg, 6 mg) and their usual inhaled nicotine product (cigarette or e-cigarette/vape) * visit the hospital research ward on 4 separate days for 8 hours each day * use one of each of the products in a randomized order (by chance, like flipping a coin) on each of the 4 hospital study days