Short-Term Cardiovascular Effects of E-Cigarettes: Influence of Device Power

Open to people ages 21 years and up

• Use e-cigarettes on at least 25 days in the past 30 for at least 3 months and have not used another tobacco product in the past 30 days
• Healthy on the basis of medical history and limited physical examination (screening visit), as described below:
• Heart rate < 105 BPM*
• Systolic Blood Pressure < 160 and > 90*
• Diastolic Blood Pressure < 100 and > 50*
• Body Mass Index ≤ 38.0 (at investigator's discretion for higher BMI if no other concurrent health issues)

*Considered out of range if both machine and manual readings are above/below these thresholds.

• Any race/ethnicity

• Used tobacco products other than e-cigarettes in past 30 days
• Expired carbon monoxide of over 5 ppm at screening
• The following unstable medical conditions:
• Heart disease
• Uncontrolled hypertension
• Thyroid disease (not hypo or hyper, controlled with medication)
• Diabetes
• Hepatitis B or C or Liver disease
• Glaucoma
• Prostatic hypertrophy
• Psychiatric conditions:
• Current or past schizophrenia, and/or current or past bipolar disorder
• Adult onset ADHD (if being treated)
• Participants with current or past depression and/or anxiety disorders will be reviewed by the study physician and considered for inclusion
• Psychiatric hospitalizations are not exclusionary, but study participation will be determined as per study physician's approval
• Drug/Alcohol Dependence:
• Alcohol or illicit drug dependence within the past 12 months with the exception of those who have recently completed an alcohol/drug treatment program
• Positive toxicology test at the screening visit (THC & prescribed medications okay)
• Opioid replacement therapy
• Positive urine cannabis is not exclusionary but participant must report use of cannabis in any form on not more than 2 times per week to be eligible
• Psychiatric medications:
• Current regular use of any psychiatric medications with the exception of SSRIs and SNRIs and current evaluation by the study physician that the participant is otherwise healthy, stable, and able to participate.
• Medications
• Use of medications that are inducers of nicotine metabolizing enzyme CYP2A6 (Example: rifampicin, dexamethasone, phenobarbital, and other anticonvulsant drugs).
• Concurrent use of nicotine-containing medications
• Other/Misc. Chronic Health Conditions
• Oral thrush
• Fainting
• Untreated thyroid disease
• Other "life threatening illnesses" as per study physician's discretion
• Pregnancy
• Pregnancy (self-reported and urine pregnancy test)
• Breastfeeding (determined by self-report)
• Concurrent participation in another clinical trial
• Inability to communicate in English
• Planning to quit smoking or vaping within the next 60 days