Electronic Nicotine Delivery Systems (ENDS), commonly referred to as electronic cigarettes have gained in popularity over the last several years. The technology used to manufacture ENDS has been evolving rapidly with a variety of delivery mechanisms, nicotine content, e-liquids and flavorings. Only in the last few years have researchers begun to examine the health risks and benefits, nicotine blood levels, patterns of use, likability, and craving and withdrawal relief of ENDS. These studies have shown great variability in nicotine delivery, effects on heart rate, and relief of craving or withdrawal among various ENDS brands among tobacco cigarette smokers.

This study will test a new generation ENDS, the NJOY King Bold (NJOY, Scottsdale, AZ). It is a single use unit that resembles a traditional cigarette and delivers approximately 150 puffs. The cartridge inside contains 26 milligrams of nicotine.

Our primary objective is to evaluate the short-term effects of using the NJOY Kings ENDS on heart rate, carbon monoxide and blood nicotine levels and well as on craving for cigarettes and nicotine withdrawal. Our secondary objective is to evaluate the subject's usage patterns for cigarettes and NJOY King ENDS during a one-week period in which they can use each freely.

The study includes three visits to the clinic spaced approximately one week apart. Subjects who pass the screening visit will return to the clinic for Visit 2 in which they will sample the NJOY King ENDS for about 20 minutes before taking home enough to last till Visit 3, one week later. They will be instructed to use as many or as few as they like during the week. Subjects will keep a daily diary of number of tobacco cigarettes smoked and number of e-cigarette puffs taken. Subjects will return to the clinic for Visit 3 after 12 hours of abstinence from any form of nicotine in order to assure that they have no nicotine left in their bloodstream. Eligible subjects will then participate in two series of 10 puffs of NJOY Kings spaced one hour apart. During the 2.5 hours of the testing day, the following will be measured: 1) heart rate, 2) carbon monoxide, 3)blood will be sampled for nicotine levels, 4) craving for cigarettes and nicotine withdrawal symptoms will be assessed.

Inclusion Criteria:

1. Healthy cigarette smokers
2. Not trying or planning to quit
3. >10 factory-produced cigarettes/day for previous year
4. Breath carbon monoxide level of >10 ppm at screening

Exclusion Criteria:

1. Pregnancy or lactation
2. Abuse of drugs other than tobacco
3. Use of any prescription psychoactive medications within 14 days
4. Use of ENDS within 14 days
5. Use of any nicotine replacement within 30 days