Vaping | Physiology homework help

Vaping I

Stephan C. Jahn, Ph.D.

Pharmacology and Therapeutics

University of Florida

Primary Source: Cao et al,
J. Med. Toxicol. (2020)

Vaping

 Well-intentioned catastrophe
 Safer

 Cessation

 Entered US market in 2006

 Vaping
 Inhalation of aerosols

 Three primary purposes
 Nicotine

 THC

 Flavor

Who Vapes?

 Nonpoor, young whites
 Especially men

 Exponential growth
 2018: 13.5% 8th graders, 34% 12th graders
 2019: 40.5% of 12th graders
 Most users 18-24

 Mixed reasons
 Young

 Social
 Flavors

 Older
 Cessation

Vaping Devices
 First generation

 One-time-use “cig-a-likes”

 Second generation
 Reusable
 Larger battery

 Third generation
 “Mods”
 Customizable

 Fourth generation
 “Pods”
 Flashdrive appearance
 Juul
 Marketed heavily to youth

Malanga and Smith
https://www.sjuhawknews.com/health-
officials-urge-students-to-stop-using-
electronic-cigarettes/

E-Liquids

 Hard to pin down
 Little regulation

 Rapidly changing market

 User refillable

 Inhaled components depend on heat generated by device
 Potential for reactions or decomposition

Nicotine E-Liquids

 Contains:
 Nicotine

 Purified

 Highly variable concentrations

 Juul has patent for nicotine acid salt to increase absorption

 Propylene glycol and/or glycerin
 Thickeners

 Water

 Flavoring

 Concentrated nicotine poses threat to toddlers

Toxicology of Thickeners

 Propylene Glycol and Glycerin

 Extremely common in food, cosmetics, and pharmaceuticals

 FDA “generally recognized as safe”

 Inhalation is a whole ‘nother ball game
 Alveoli very delicate

 Decomposition products
 i.e. acrolein

 Two studies show vaping thickeners alone causes epithelial injury and
decreased oxygen absorption

Other E-Liquids

 THC
 Similar to nicotine e-liquids in constituency

 Even more variability due to illicit nature

 More likely to contain vitamin-E acetate

 Used by ~20% of cannabis users

 Alcohol/caffeine
 Dosages are small compared to normal consumption

 Still dangers due to excipients

 Other illicit drugs

 Flavors only

Vaping Pharmacokinetics

 Best studied with nicotine

 One session administers an average of 4 mg
 3-4x one cigarette

 Plasma concentration plateaus around 13 ng/mL
 Roughly equal to one cigarette

 Slower climb

 Less addictive?

St Helen G, Ross KC, Dempsey DA, Havel CM, Jacob P 3rd, Benowitz NL. Nicotine Delivery and Vaping Behavior
During ad Libitum E-cigarette Access. Tob Regul Sci. 2016;2(4):363‐376. doi:10.18001/TRS.2.4.8