Reference

Vaping & quit-vaping glossary

Definitions for every term used across the PuffPause blog, the chemistry, the devices, and the behaviour-change vocabulary. Each entry links to the deepest related guide.

Abstinence violation effect

The all-or-nothing reaction after a single slip that turns a slip into a full relapse.

Naming this effect out loud after a slip is one of the most protective things a quitter can do.

Bupropion (Zyban / Wellbutrin)

A prescription antidepressant repurposed as a cessation aid; reduces cravings and blunts withdrawal.

Bupropion suits people with concurrent low mood or ADHD; it is contraindicated in seizure disorders and eating disorders.

CBT (cognitive behavioural therapy)

Structured talk therapy that identifies craving triggers and rewires the thoughts that follow them.

CBT is the behavioural backbone of most evidence-based cessation programmes; a handful of sessions is enough.

Cessation

The clinical term for stopping tobacco or nicotine use.

Cessation research is where most of what we know about withdrawal timelines and quit success comes from.

Cold turkey

Stopping nicotine completely on a chosen day rather than tapering.

Cold turkey has a shorter total withdrawal window but a harder first week; both approaches have comparable long-term quit rates.

Combination NRT

Using a long-acting patch together with a short-acting form (gum, lozenge, or spray) for breakthrough cravings.

Combination NRT outperforms single-form NRT in Cochrane meta-analyses and is the first-line approach in NHS Stop Smoking Services.

Cotinine

The main metabolite of nicotine. Detectable in urine, saliva, and blood for two to three days after the last exposure.

Cotinine is the marker labs use to confirm nicotine use because it clears more slowly than nicotine itself.

Craving

A short, cue-triggered urge to vape. Individual cravings peak and pass in three to five minutes.

Frequency is what changes over time, not craving intensity itself.

Cue / trigger

A person, place, feeling, or action the brain has learned to pair with vaping: coffee, a car, stress, a phone unlock.

Most first-month relapses are cue-driven, not withdrawal-driven. Changing the cue often works when willpower does not.

Cue reactivity

The measurable physical and mental response (heart rate, attention, craving) that a learned cue triggers.

Cue reactivity fades with repeated cue exposure without vaping. This is the mechanism behind "urge surfing."

Cytisine (Tabex)

A plant-derived partial nicotinic agonist, similar mechanism to varenicline. Available OTC in parts of Europe.

Cytisine has one of the best cost-per-quit ratios in the WHO analyses. Not yet FDA-approved in the US as of 2026.

Diacetyl

A buttery flavour compound linked to bronchiolitis obliterans ("popcorn lung") when inhaled at industrial levels.

Diacetyl was found in early e-liquids and has been largely removed from regulated markets, but is still worth checking on grey-market disposables.

Disposable vape

A single-use device with battery, coil, and e-liquid built in. Typically 20 mg/mL nicotine salt, 600-5,000 puffs.

Disposables are the format that pushed daily nicotine intake sharply up for many users in the last five years.

Dopamine

The neurotransmitter released in the mesolimbic reward pathway when nicotine binds nAChRs.

The nicotine dopamine hit is small compared with cocaine, but its short cycle and reliability are what make it habit-forming.

Dual use

Regular use of both cigarettes and vapes, rather than fully switching.

Dual users lose most of the harm-reduction benefit of switching; cessation guidance treats it as a transitional state, not an endpoint.

EVALI

E-cigarette or vaping product use-associated lung injury. A cluster of severe lung injuries first identified in 2019.

Investigations traced most EVALI cases to vitamin E acetate in illicit THC vape cartridges, not nicotine e-liquids from regulated markets.

Extinction

The learning process by which a cue stops predicting a reward, weakening its power to trigger a craving.

Extinction is why the third week is usually easier than the first, the cue-craving link is decaying.

FDA PMTA

Premarket Tobacco Product Application, the FDA process a vape product must pass to be legally sold in the US.

Very few flavoured disposable vapes hold current PMTA authorisation. Most of what is sold in US convenience stores is unauthorised.

Formaldehyde

A carcinogen that can form when e-liquid is over-heated on dry or high-power coils.

Formaldehyde levels in normal-use vaping are far below combusted tobacco, but rise sharply with dry hits and sub-ohm chain vaping.

Freebase nicotine

The older, unprotonated form of nicotine used in most refillable tanks. Harsher at high strengths, which naturally capped how much users inhaled.

Most 3 mg/mL and 6 mg/mL bottled e-liquids are freebase; disposables and pods are almost always nicotine salts.

Half-life

The time for the body to eliminate half of a dose. Nicotine's half-life is roughly two hours.

Short half-life is why craving cycles feel so tight, the brain is asking for the next dose two hours after the last one.

Harm reduction

A public-health approach that prioritises lowering damage from a behaviour when full abstinence is not immediate.

Switching a heavy smoker to vaping is harm reduction; staying on a lower-strength vape indefinitely is a common harm-reduction endpoint but not the same as cessation.

HPHCs (harmful and potentially harmful constituents)

The FDA's list of chemicals in tobacco and vapour products that pose a known or suspected health risk.

Vaping produces far fewer HPHCs than combusted tobacco, which is the basis of most harm-reduction claims for switching smokers.

mAh

Milliamp-hours, a rating of battery capacity, not nicotine.

A 550 mAh disposable roughly matches its e-liquid capacity; a much higher mAh number rarely means more nicotine.

Mesh coil

A perforated metal strip used in place of a coiled wire, with more even heating and more vapour per puff.

Mesh is why modern disposables deliver noticeably more nicotine per draw than older wire-coil devices at the same strength.

Mesolimbic pathway

The brain reward circuit running from the ventral tegmental area to the nucleus accumbens. The main site of nicotine's reinforcing effect.

Every addictive drug converges on this pathway; nicotine is unusual in how briefly and repeatedly it activates it.

mg/mL vs %

Two ways to label nicotine strength. 20 mg/mL and 2% are the same concentration.

The US usually labels vapes in %, most of Europe and Australia in mg/mL. Multiply % by 10 to get mg/mL.

MHRA

The UK Medicines and Healthcare products Regulatory Agency, which registers e-cigarette products in the UK.

The MHRA notification list is the closest thing to a public registry of legal UK e-liquids and devices.

nAChR (nicotinic acetylcholine receptor)

The receptor nicotine binds to. Drives dopamine release in the reward pathway and shapes how dependence forms.

Chronic nicotine multiplies these receptors; recovery is largely the receptor count returning to baseline over 3-4 weeks.

Nicotine

The addictive stimulant found in tobacco and most vapes. It binds to nicotinic acetylcholine receptors and triggers a small dopamine release.

Nicotine itself is not what causes cancer in cigarettes, combustion is, but it is what makes both vapes and cigarettes addictive.

Nicotine salts

A protonated form of nicotine (usually with benzoic acid) that is less harsh to inhale at high concentrations, letting vapes deliver much more nicotine per puff.

Nicotine salts are the reason modern pod and disposable vapes routinely contain 20-50 mg/mL, several times what early e-cigarettes delivered.

NRT (nicotine replacement therapy)

Regulated nicotine products: patches, gum, lozenges, sprays, and inhalers, used to blunt withdrawal without inhaling.

NRT roughly doubles quit success in smokers; the same clinical evidence base is now being used for vapers.

PG (propylene glycol)

One of the two main solvents in e-liquid. Carries flavour and produces the throat hit.

Higher PG ratios feel sharper in the throat and produce less visible vapour.

Pod

A refillable or replaceable cartridge that attaches to a small battery. Popularised by Juul.

Pods run cooler and typically use nicotine salts, so a small device can still deliver a high nicotine dose.

Priming

A single puff after quitting sharply increases the probability of another puff within 24 hours.

Priming is the pharmacology behind the abstinence-violation effect: the nicotine dose itself makes the next dose more likely.

Quit date

A pre-committed calendar date on which nicotine use stops.

Setting a date within 2-4 weeks outperforms both "someday" and "tomorrow," the interval is what predicts follow-through.

Quitline

A free, telephone-based counselling service for people quitting tobacco or vaping.

The US quitline is 1-800-QUIT-NOW; the UK equivalent is the NHS Smokefree helpline. Both offer free NRT in many regions.

Receptor upregulation

The brain's response to chronic nicotine: more nicotinic receptors, more sensitive to it.

Upregulation is what makes early withdrawal feel worse than expected; it normalises within about a month of not vaping.

Relapse

Returning to regular vaping after quitting. A single slip is not the same thing.

A slip becomes a relapse when the next cue is treated as permission to keep going. Naming that moment is the intervention.

SmokefreeTXT / This Is Quitting

Free daily-SMS behavioural support programmes from Truth Initiative and the US National Cancer Institute.

This Is Quitting is the most-studied vape-specific text program, with published effect sizes in young adults.

Taper

Gradually reducing daily nicotine, through lower-strength liquid or scheduled puff reductions, before stopping.

A structured taper works best when it is shorter than four weeks and enforced by a schedule, not by feel.

TGA

Australia's Therapeutic Goods Administration. Regulates nicotine vapes as prescription-only in AU.

As of 2024, adults in Australia need a doctor's prescription to legally buy nicotine e-liquid, and only pharmacies dispense it.

Throat hit

The scratchy sensation at the back of the throat when inhaling nicotine. A behavioural cue as much as a physical one.

Losing throat hit is one of the underrated triggers in the first quit week, the mouth expects a sensation that never arrives.

Tolerance

Needing more nicotine to get the same effect. Builds within days of regular use.

Tolerance is why casual weekend vaping so often turns into daily use inside a month.

TPD (Tobacco Products Directive)

The EU regulation capping e-liquid nicotine at 20 mg/mL and tank size at 2 mL, and requiring safety notifications.

TPD is why UK and EU disposables usually top out at 20 mg/mL, versus 50 mg/mL in unregulated markets.

Varenicline (Chantix / Champix)

A prescription partial agonist at the α4β2 nicotinic receptor. Reduces both cravings and the reward from a slip.

Varenicline has the largest effect size of any single monotherapy in cessation trials. Prescribers monitor mood and sleep in the first weeks.

VG (vegetable glycerin)

The other main e-liquid solvent. Thicker than PG and responsible for most of the visible vapour cloud.

High-VG blends are smoother but need more power to vaporise.

Withdrawal

The physical and mood symptoms that follow stopping nicotine after regular use: irritability, restlessness, poor focus, poor sleep, headaches, appetite change.

Withdrawal typically peaks on days two to four and largely resolves within two to four weeks.