Withdrawal Symptoms from E-Cigarette Abstinence Among Adult Never-Smokers: A Pilot Experimental Study.

INTRODUCTION: Use of e-cigarettes among never-smokers has substantially increased; yet there are few descriptions of the consequences of such use. We assessed whether adult never-smokers can have withdrawal from cessation of e-cigarettes. METHODS: In an un-blinded pre-post clinical trial, 30 never-smoker daily e-cigarette users used their own nicotine-containing e-cigarette for 7 days followed by 6 days of biologically confirmed abstinence. Participants monitored symptoms of nicotine withdrawal nightly via an Interactive Voice Response system. They attended three lab visits/week to provide expired carbon monoxide and urine samples to determine compliance. FINDINGS: Abstinence increased all the DSM5 symptoms of tobacco withdrawal and this occurred in the majority of participants. The increase in severity of withdrawal was small and rarely impaired functioning. CONCLUSIONS: Our finding suggests that withdrawal symptoms can occur in never-smokers who stop e-cigarettes abruptly. However, the severity of withdrawal appears to be small and may not be of clinical or regulatory significance. Although our sample size was small and thus replication tests of our results are indicated, it may be prudent to warn never-smokers that withdrawal symptoms may occur. IMPLICATIONS: This study indicates that withdrawal symptoms can occur in never-smokers who are daily e-cigarette users. However, the severity of withdrawal from e-cigarette abstinence in never-smokers appears to be small and may not be of clinical or regulatory significance. Given our small sample size, replication of our results is warranted. Nevertheless, it might be prudent to warn never-smokers of addiction to e-cigarettes.Clinical Trial Registration = NCT02825459.