Self-titration by experienced e-cigarette users: blood nicotine delivery and subjective effects

Introduction:
This text is a summary of a scientific study examining the effects of high and low nicotine strength liquid on puffing topography, nicotine delivery, and subjective effects in experienced e-cigarette users. The study aims to understand how e-cigarette users adjust their puffing behavior and nicotine intake in response to different nicotine concentrations.

Key Points:

* The study used a double-blind within-participants, counterbalanced design with two conditions: low (6 mg/mL) and high (24 mg/mL) nicotine concentration liquid.
* Eleven regular e-cigarette users (all male ex-smokers) participated in two separate sessions, vaping ad libitum for 60 minutes.
* Measurements included puffing topography (puff number, puff duration, volume of liquid consumed), plasma nicotine levels, craving, withdrawal symptoms, self-reported hit, satisfaction, and adverse effects.
* Liquid consumption and puff number were higher, and puff duration was longer, in the low nicotine strength condition.
* Mean nicotine boost from baseline was significantly higher in the high nicotine condition at 10, 30, and 60 minutes.
* There were no significant differences in self-reported craving, withdrawal symptoms, satisfaction, hit, or adverse effects between conditions.
* Participants doubled their liquid consumption in the low versus high nicotine condition, indicating compensatory puffing behavior.

Main Message:
The main message of this study is that experienced e-cigarette users engage in compensatory puffing, increasing their puff frequency and duration and consuming more liquid when using a lower nicotine strength liquid. While this behavior reduces craving and withdrawal symptoms, it is not fully effective in achieving complete self-titration, leading to significantly higher plasma nicotine levels in the high nicotine condition. These findings have implications for e-cigarette users who may switch to lower nicotine strength liquids due to regulatory changes or personal preferences, as they may increase their liquid consumption and potentially expose themselves to higher levels of toxins and carcinogens.

Dawkins, Lynne E., Catherine F. Kimber, Mira Doig, Colin Feyerabend, and Olivia Corcoran. “Self-Titration by Experienced e-Cigarette Users: Blood Nicotine Delivery and Subjective Effects.” Psychopharmacology 233, no. 15–16 (August 2016): 2933–41. https://doi.org/10.1007/s00213-016-4338-2.