Epinephrine, over-the-counter inhaled bronchodilator

What it is

This is an aerosol inhaler, bought without a prescription in the United States, that puts 0.125 mg of epinephrine into the mouth and airways per spray. Its labelled purpose is as a bronchodilator. It is a reformulation of a product sold for about fifty years with a chlorofluorocarbon propellant; the sponsor's own trial report describes the new version as changed to a hydrofluoroalkane propellant, changed from a solution to a suspension and reduced in dose by 43%. The ingredient is one of those the FDA listed in 1986 as permitted bronchodilator active ingredients for over-the-counter products.

What the research says

Inhaled epinephrine does open the airways: the sponsor's own dose-ranging trials showed a measurable rise in FEV1 against placebo at doses above 125 mcg, and a sponsor-run trial in two 3-month stages found it broadly comparable to the older product on its Stage 1 efficacy endpoint at Week 12. All of that evidence is industry-funded and there is no independent placebo-controlled trial of the reformulated inhaler here. What is disputed is whether that makes it a sensible thing to sell over the counter for asthma. Respiratory-medicine authors writing in a major journal in 2023 described the evidence that it matches a beta-2 selective reliever as only low quality, and argued that a more selective drug would be safer. The sponsor's own authors record that asthma guidelines do not recommend epinephrine for asthma except alongside anaphylaxis or angioedema, and separately, the background of a 2024 cost-effectiveness modelling paper states that using inhaled epinephrine without an inhaled corticosteroid may increase the risk of asthma death. Nothing in this entry is about the epinephrine injector used for a severe allergic reaction, which is a different route, a different dose and a different evidence base.

Evidence grade: Disputed.

How it works

Drug class: Non-selective alpha- and beta-adrenergic agonist (catecholamine) used as an inhaled bronchodilator

Epinephrine switches on both families of adrenergic receptors rather than picking one. The sponsor-affiliated review passage states that it raises cardiac output by stimulating beta-1 receptors in the heart and narrows blood vessels by activating alpha-1 receptors, and that this lack of selectivity is the reason its cardiovascular effects are a concern. The same paper's discussion argues that when the drug is inhaled it lands mostly in the airways, where beta-2 receptors on bronchial smooth muscle predominate, so relaxing the airway muscle is the effect that dominates and the effect on cardiac output is reduced. (Source 1)

What it is used for

• The sponsor's own single-dose crossover trials reported FEV1 gains over placebo at doses above 125 mcg per dose. A separate sponsor-run trial ran as two 3-month randomised stages and assessed bronchodilator efficacy in Stage 1 only, at Week 12; it reported the new inhaler and the old chlorofluorocarbon product as overall comparable in bronchodilator efficacy; neither trial was independent and we found no independent placebo-controlled trial of the reformulated inhaler. Independent respiratory-medicine authors writing in 2023 call the evidence that it matches a beta-2 selective reliever only low quality, and the background of a 2024 cost-effectiveness paper states that inhaled epinephrine used without an inhaled corticosteroid may increase the risk of asthma death. Evidence: disputed. (Source 2)
• The label itself does not support this: it tells people to see a doctor if they are not better in 20 minutes, if they get worse, if they need more than 8 inhalations in 24 hours, or if they have more than 2 attacks in a week, and it lists difficulty sleeping, a rapid heart beat, tremors, nervousness or seizure as reasons to stop. Authors affiliated with the manufacturer also record that asthma guidelines do not recommend epinephrine for asthma except where there is anaphylaxis or angioedema at the same time. Evidence: not-supported. (Source 3)

Interactions

• Monoamine oxidase inhibitors (MAOIs) (label): The label's strongest instruction: the product is not to be used by anyone taking a prescription MAOI, or within two weeks of stopping one. MAOIs block the enzyme that breaks catecholamines down, so adding a sympathomimetic drug risks an exaggerated cardiovascular response. (Source 4)
• Caffeine in food and drink (label): The label tells people using the inhaler to avoid caffeinated food and drink. Caffeine is a stimulant and the concern is additive stimulant effect on heart rate and jitteriness. This is a labelling instruction, not the result of an interaction study. (Source 5)
• Dietary supplements with stimulant ingredients (label): The label tells people to avoid supplements whose ingredients are reported or claimed to be stimulants. It names no specific supplement, so this is a class-level labelling caution rather than evidence about any particular product. (Source 5)
• Other decongestants and stimulant-containing medicines (phenylephrine, pseudoephedrine, ephedrine, caffeine-containing products) (label): The label directs anyone taking a medicine containing these to ask a doctor or pharmacist first. They act on the same adrenergic system, so the effects can stack. (Source 6)
• Prescription asthma, weight-control and psychiatric medicines (label): The label directs anyone already on prescription drugs for asthma, obesity, weight control, depression or psychiatric or emotional conditions to ask a doctor or pharmacist before using it. For asthma drugs in particular the concern is doubling up on relievers without anyone supervising. (Source 6)
• Inhaled corticosteroids (the risk is in their absence rather than in combining them) (theoretical): The documented concern is not that the two clash, it is that people buying a reliever over the counter may use it without any steroid inhaler at all. A 2024 paper states that inhaled epinephrine used without an inhaled corticosteroid may increase the risk of dying from asthma. (Source 7)

Stopping it

• Nothing in the trials describes a withdrawal syndrome or a taper for this inhaler. The six-month safety study, run as two 3-month randomised stages, reported only non-serious adverse events and no clinically relevant changes in vital signs, ECG, glucose or potassium, and reported nothing about stopping. (Source 8)
• The label's position on when to stop is about the asthma, not about the drug: getting worse, needing it too often, or developing stimulant symptoms are all reasons it lists for seeing a doctor rather than carrying on. (Source 9)
• The Warnings section sets the thresholds that count as the asthma getting worse, including needing more than 8 inhalations in 24 hours or having more than 2 attacks in a week. (Source 3)

What goes wrong

The same authors tie historical asthma mortality epidemics to high-dose, poorly selective beta agonists and say greater beta-2 selectivity is a potential safety advantage over epinephrine. (Source 10)

• Expert review, not systematic, Low certainty.
• Size: not applicable.
• Who: people with asthma using reliever inhalers.
• How long: not applicable.
• Result: No rate given for epinephrine itself; the comparison is framed as a potential safety advantage of a more selective drug.
• Funding: not stated.

Furthermore, as asthma mortality epidemics have been associated with high-dose preparations of poorly selective β2 agonists, the relatively lower β2-agonist dose of ICS/formoterol may have a potential safety advantage when compared with albuterol, and the greater β2-agonist selectivity a potential safety advantage compared with epinephrine.

A 2024 paper in a US allergy journal states that inhaled epinephrine used without an inhaled corticosteroid may raise the risk of dying from asthma. (Source 7)

• Expert review, not systematic, Very low certainty.
• Size: not applicable (background statement introducing a modelling study)
• Who: US adults with mild asthma and no prescription inhaler.
• How long: not applicable.
• Result: No measured rate; the paper's own modelled estimate is reported separately under disagreements.
• Funding: not stated in the abstract.

However, inhaled epinephrine use without an inhaled corticosteroid may increase the risk of asthma death.

Adverse events in the dose-ranging trials were about twice as frequent on the epinephrine inhaler as on placebo, and three severe events all occurred in epinephrine arms. (Source 11)

• Randomized trial, Low certainty.
• Size: 71 adverse events across 358 treatments in 56 subjects.
• Who: adults with intermittent or mild-to-moderate persistent asthma in two crossover trials.
• How long: single doses.
• Result: 48 (22%) adverse events with epinephrine HFA, 6 (11%) with placebo and 17 (20%) with epinephrine CFC; all non-serious; three severe events in the epinephrine HFA arms, one of them (feeling jittery) judged likely related to the drug.
• Funding: industry-funded (Amphastar Pharmaceuticals, Inc. funded the two dose-ranging studies and the preparation of the article, including all article processing charges; the study drugs were provided by its subsidiary Armstrong Pharmaceuticals, Inc.)

A total of 71 AEs were reported during the dose-ranging trials, including 48 (22%), 6 (11%), and 17 (20%) AEs for Epi-HFA, PLA, and Epi-CFC treatments, respectively.

The commonest side effects in those trials were headache, a taste disturbance and feeling jittery, and they clustered in the epinephrine arms rather than on placebo. (Source 12)

• Randomized trial, Low certainty.
• Size: 29 of the 71 adverse-event reports.
• Who: adults with asthma in two crossover trials.
• How long: single doses.
• Result: Headache 11 events (9 epinephrine HFA, 2 epinephrine CFC); dysgeusia 10 events (5 epinephrine HFA, 1 placebo, 4 epinephrine CFC); feeling jittery 8 events (7 epinephrine HFA, 1 epinephrine CFC); together 41% of all adverse events.
• Funding: industry-funded (Amphastar Pharmaceuticals, Inc. funded the two dose-ranging studies and the preparation of the article, including all article processing charges; the study drugs were provided by its subsidiary Armstrong Pharmaceuticals, Inc.)

The three most common AEs reported with an incidence ≥3.0% in any treatment arm were headache (n = 11), dysgeusia (n = 10), and feeling jittery (n = 8).

The product's own label warns that it can raise blood pressure or heart rate and that this could increase the risk of heart attack or stroke, which may cause death, and that the risk rises with pre-existing heart disease or with using more than directed. (Source 5)

• Official position, Certainty not rated.
• Size: not applicable.
• Who: people buying the inhaler over the counter in the US.
• How long: label version published 23 June 2026.
• Result: No rate given on the label.
• Funding: not applicable.

■ your blood pressure or heart rate may go up. This could increase your risk of heart attack or stroke, which may cause death.

The label also lists the symptoms that should stop use, which are the recognisable stimulant effects of the drug. (Source 9)

• Official position, Certainty not rated.
• Size: not applicable.
• Who: people using the inhaler over the counter.
• How long: label version published 23 June 2026.
• Result: Difficulty sleeping, rapid heart beat, tremors, nervousness or seizure.
• Funding: not applicable.

■ you have difficulty sleeping ■ you have a rapid heart beat ■ you have tremors, nervousness, or seizure

The product's label tells anyone who is pregnant or breast-feeding to ask a health care professional before using it. (Source 13)

• Official position, Certainty not rated.
• Size: not applicable.
• Who: people buying the inhaler over the counter in the US.
• How long: label version published 23 June 2026.
• Result: No rate or outcome given; the label states only that a health care professional should be asked first.
• Funding: not applicable.

If pregnant or breast-feeding, ask a health care professional before use

The label's Warnings section also tells people to keep the inhaler out of reach of children and, in case of overdose, to get medical help or contact a Poison Control Center right away. (Source 14)

• Official position, Certainty not rated.
• Size: not applicable.
• Who: households where the inhaler is kept.
• How long: label version published 23 June 2026.
• Result: No rate given; the label treats overdose as a reason for immediate medical help.
• Funding: not applicable.

Keep out of reach of children. In case of overdose, get medical help or contact a Poison Control Center right away.

What the evidence supports

In the sponsor's single-dose crossover trials, the inhaler improved lung function more than placebo at doses above 125 mcg, and the paper reports efficacy at 125 to 250 mcg as comparable to the older chlorofluorocarbon product. (Source 2)

• Randomized trial, Low certainty.
• Size: 56 subjects across two crossover trials (26 in trial A1, 30 in trial A2); 358 treatments analysed for safety.
• Who: adults aged 18 to 55 with intermittent or mild-to-moderate persistent asthma, mean FEV1 about 68% of predicted.
• How long: single doses, spirometry over 6 hours, visits 2 to 14 days apart.
• Result: Statistically significant improvement in FEV1 over placebo at all doses above 125 mcg out of the actuator; efficacy at 125 to 250 mcg comparable to epinephrine CFC at 220 mcg per inhalation.
• Funding: industry-funded (Amphastar Pharmaceuticals, Inc. funded the two dose-ranging studies and the preparation of the article, including all article processing charges; the study drugs were provided by its subsidiary Armstrong Pharmaceuticals, Inc.)

Limit of this finding: The abstract we quote says the improvements were significant at all doses above 125 mcg, but the same paper's own efficacy table shows the 125 mcg arm itself was significant (p < 0.0001) while 90 mcg was not (p = 0.1404). The wording is the abstract's, not ours, and we have kept it; read the "above 125 mcg" threshold as the abstract's summary rather than as the dose below which the inhaler did nothing.

Spirometry testing for FEV1 (Forced Expiratory Volume in one second) demonstrated statistically significant improvements over PLA for epinephrine HFA MDI at all doses above 125 μg, as the amount out of the actuator (i.e., mouthpiece).

The six-month safety study, run as two 3-month stages, reported tremor as the commonest adverse event on the epinephrine inhaler, with no serious events and no clinically relevant changes in vital signs, ECG, glucose or potassium. (Source 8)

• Randomized trial, Low certainty.
• Size: two 3-month stages in people aged 12 and over.
• Who: people with intermittent or mild-to-moderate persistent asthma.
• How long: 6 months.
• Result: No rates given in the abstract; tremor most commonly reported for epinephrine HFA; all adverse events non-serious.
• Funding: industry-funded (manufacturer-sponsored development programme for the reformulated product; the abstract carries no funding statement, and three of its ten authors - T. Marrs, M.Z. Luo and J.Y. Zhang - are disclosed as Amphastar employees owning company stock in the manufacturer's later pharmacokinetic study of the same inhaler)

Both also showed low incidence rates of AEs with tremor being most commonly reported for epinephrine HFA. All AEs found were non-serious and non-significant.

An industry-funded crossover study in healthy adults found inhaled epinephrine produced far lower systemic drug levels than an intramuscular injection or an albuterol inhaler, with no meaningful cardiovascular changes. (Source 15)

• Blood level study, Low certainty.
• Size: 28 healthy adult subjects.
• Who: 28 healthy adult volunteers aged 18 to 50 without clinically significant disease; the paper does not report whether any had asthma - in a randomised, evaluator-blinded three-arm crossover.
• How long: single doses, blood sampling across each crossover visit.
• Result: Exogenous exposure 39 pg/mL x hour for inhaled epinephrine, 435 for intramuscular epinephrine and 3453 for the albuterol inhaler; those are the raw exposures, a ratio of 11.2 times and 88.5 times, and it is the ratios the paper reports after dose normalisation as about 9 times and 122 times lower. Cmax 345 pg/mL against 816 and 681; plasma levels back to baseline in about 0.6 hour.
• Funding: industry-funded (Amphastar Pharmaceuticals, Inc. funded the pharmacokinetic study and the preparation of the article; four of the five authors have an Amphastar financial relationship - three are company employees who own stocks or shares, a fourth has served as a consultant and clinical advisory board member, provided medical writing assistance, and received stock options and travel reimbursement - and only the fifth declares none)

Limit of this finding: This is a single-dose study in 28 healthy adult volunteers rather than in a population selected for asthma, so its reassuring safety reading applies to those volunteers and that one dose. It was funded by the manufacturer and four of its five authors have a financial relationship with the manufacturer.

Epinephrine MDI and albuterol MDI resulted in minimal, clinically insignificant changes in vital signs and ECGs, whereas epinephrine IM led to mild transient increases in systolic blood pressure, heart rate, and corrected QT interval.

What the evidence does not support

The authors of those trials state their own limitations: the groups were small and only single doses of one or two puffs were tested, so they could not speak to repeated use. (Source 16)

• Randomized trial, Low certainty.
• Size: 21 to 25 subjects in each dosing group.
• Who: adults with intermittent or mild-to-moderate persistent asthma.
• How long: single dose only.
• Result: No long-term efficacy or safety estimate from these trials.
• Funding: industry-funded (Amphastar Pharmaceuticals, Inc. funded the two dose-ranging studies and the preparation of the article, including all article processing charges; the study drugs were provided by its subsidiary Armstrong Pharmaceuticals, Inc.)

The numbers of subjects for these trials were small, with 21–25 subjects in each dosing group.

Respiratory-medicine authors writing in the American Journal of Respiratory and Critical Care Medicine in 2023 described the evidence that over-the-counter aerosolised epinephrine matches a selective reliever as only low quality. (Source 17)

• Expert review, not systematic, Low certainty.
• Size: not applicable (editorial commentary, no stated search or pooling method)
• Who: adolescents and adults with asthma in the United States.
• How long: not applicable.
• Result: No effect estimate given; the authors characterise the evidence base as low quality.
• Funding: not stated.

such an action would provide a much-needed safer and more effective choice to the current OTC availability of aerosolized epinephrine, an α and β agonist, for which there is only low-quality evidence that it has similar efficacy as a β2-selective agonist

Investigators affiliated with the manufacturer record that asthma guidelines do not recommend epinephrine for asthma unless anaphylaxis or angioedema is present at the same time. (Source 1)

• Blood level study, Low certainty.
• Size: not applicable (the sentence is from the Introduction of an industry-funded Phase IV randomised, evaluator-blinded crossover pharmacokinetic trial, not a result of it)
• Who: people with asthma.
• How long: not applicable.
• Result: No effect estimate; a statement of the guideline position.
• Funding: industry-funded (Amphastar Pharmaceuticals, Inc. funded the pharmacokinetic study and the preparation of the article; four of the five authors have an Amphastar financial relationship - three are company employees who own stocks or shares, a fourth has served as a consultant and clinical advisory board member, provided medical writing assistance, and received stock options and travel reimbursement - and only the fifth declares none)

Limit of this finding: This sentence comes from the Introduction of the manufacturer's pharmacokinetic trial, where its authors restate what asthma guidelines say. It is not a result of that trial and we have not read the guidelines themselves, so read it as the authors' report of the guideline position. No value on this pipeline's design list describes an introductory restatement of someone else's guideline; the label records the host paper's own design.

Therefore, the use of epinephrine is not recommended by the asthma guidelines except in the context of concomitant acute asthma and anaphylaxis or angioedema.

Where the evidence is mixed

In Stage 1 of the two-stage randomised trial the new inhaler's week-12 bronchodilator efficacy closely paralleled the old chlorofluorocarbon product's, and the trial reported the two as overall comparable. (Source 8)

• Randomized trial, Low certainty.
• Size: two 3-month stages; subjects aged 12 and over randomised to epinephrine HFA, placebo HFA or epinephrine CFC.
• Who: people aged 12 or over with intermittent or mild-to-moderate persistent asthma.
• How long: 6 months in two 3-month stages, bronchodilator efficacy assessed in stage 1.
• Result: Primary efficacy endpoint (the area under the curve over 6 hours of the percentage change in FEV1 at Week 12) 47.3 +/- 54.2 for epinephrine HFA against 41.0 +/- 43.4 for epinephrine CFC; the abstract states the stages were placebo and active controlled but gives no comparison hierarchy and no non-inferiority margin, and reports no end-of-study comparison against placebo.
• Funding: industry-funded (manufacturer-sponsored development programme for the reformulated product; the abstract carries no funding statement, and three of its ten authors - T. Marrs, M.Z. Luo and J.Y. Zhang - are disclosed as Amphastar employees owning company stock in the manufacturer's later pharmacokinetic study of the same inhaler)

Both groups were found to be overall comparable in bronchodilator efficacy.

The pharmacokinetic study that underpins the manufacturer's safety case was funded by the manufacturer, and its own disclosure statement records that three authors were company employees owning company stock and a fourth had served as a consultant and clinical advisory board member, had provided medical writing assistance, and had received stock options and travel reimbursement from it. (Source 18)

• Blood level study, Certainty not rated.
• Size: 5 authors, 1 study.
• Who: not applicable.
• How long: not applicable.
• Result: Four of the five authors declare an Amphastar financial relationship; one declares none.
• Funding: industry-funded (the disclosure quoted here is the paper's own)

J.Y.Z., M.Z.L., and T.M. are employees of Amphastar at the time of the study and article preparation and own stocks/shares in Amphastar.

Where the research disagrees

Whether an over-the-counter epinephrine inhaler should be available for asthma at all

• Beasley and colleagues, editorial in the American Journal of Respiratory and Critical Care Medicine (2023), journal editorial, an expert commentary with no stated search or pooling method: "ICS/formoterol reliever alone would overcome the real concerns with the use of epinephrine taken without concomitant ICS therapy, ensuring that all patients received an ICS at the same time that their reliever was administered" (Source 17)
• Investigators affiliated with the manufacturer, Journal of Aerosol Medicine and Pulmonary Drug Delivery (2025), industry-funded randomised, evaluator-blinded three-arm crossover pharmacokinetic study in 28 healthy adult volunteers aged 18 to 50 (the paper does not state whether any had asthma); the manufacturer funded the study and the article and four of the five authors declare a financial relationship with it: "The lower SDE of inhaled epinephrine also correlated with reassuring safety findings, with no significant cardiovascular adverse effects found, compared with transient effects seen after IM epinephrine." (Source 19)
• Cost-effectiveness modellers, Annals of Allergy, Asthma and Immunology (2024), probabilistic Markov decision-analytic model over a lifetime horizon, with inputs taken from the SYGMA trials and published literature, not a head-to-head trial of the two inhalers: "Adults using as-needed budesonide-formoterol had 145 more well-controlled asthma days, 2.79 fewer severe exacerbations, and an absolute risk reduction of 0.23% for asthma-related death compared with inhaled epinephrine over a patient lifetime." (Source 20)

How much

• Reference intake: There is no prescriber here: this is an over-the-counter product, so the amount is fixed by the Drug Facts label rather than individualised. The label states it is for adults and children 12 and over, that children under 12 should not use it because it is not known whether the drug works or is safe in them, and that there should be at least 4 hours between doses. Recorded as the manufacturer's labelled position, not as advice. (Source 21)
• Upper limit: The label's ceiling is a maximum of 8 inhalations in 24 hours, and the Warnings section treats needing more than that as a reason to see a doctor rather than as a higher permitted dose. (Source 21)
• Studied: The sponsor's dose-ranging trials tested single doses from 90 to 440 mcg per dose against placebo and against the old chlorofluorocarbon product at 220 mcg per inhalation. (Source 22)
• Studied: The long-term safety study ran as two 3-month stages and randomised people in each stage to 2 x 125 mcg per inhalation of the new inhaler, placebo, or 2 x 220 mcg per inhalation of the old one. (Source 23)
• Studied: The pharmacokinetic comparison gave two inhalations of 0.125 mg each, against a 0.3 mg intramuscular epinephrine injection and two inhalations of 0.09 mg albuterol. (Source 15)

A common belief, and what the research shows

The belief: An over-the-counter epinephrine inhaler is the same as the adrenaline injector used for a severe allergic reaction, so it can be relied on in an emergency.

What the research shows: They are not the same exposure. A crossover study in 28 healthy adults measured "Systemic exogenous drug exposure for inhaled epinephrine MDI (39 pg/mL × hour) was ∼9 times lower than that of epinephrine IM (435 pg/mL × hour) and 122 times lower than that of albuterol MDI (3453 pg/mL × hour) after dose normalization." Lower systemic exposure is the point of the inhaled route, and it is also why it is not a substitute for an injection. Those multiples are the dose-normalised ratios; the raw exposures stand in a ratio of 11.2 and 88.5. The same authors, four of whose five declare a financial relationship with the manufacturer and three of whom were its employees, record that "Therefore, the use of epinephrine is not recommended by the asthma guidelines except in the context of concomitant acute asthma and anaphylaxis or angioedema."

Questions and answers

What is it?

It is a small pressurised inhaler sold without a prescription in the United States that sprays epinephrine, the same hormone the body calls adrenaline, into the airways. Each spray delivers 0.125 mg. The label describes its purpose as a bronchodilator and its use as temporary relief of mild symptoms of intermittent asthma. (Source 24)

What does it do in the body?

Epinephrine switches on both alpha and beta adrenergic receptors rather than targeting one. It raises cardiac output through beta-1 receptors in the heart and narrows blood vessels through alpha-1 receptors. When it is inhaled rather than injected, most of it reaches the airways, where beta-2 receptors on the airway muscle predominate, so the dominant effect is relaxing that muscle and opening the airway. (Source 1)

Is it good or bad for you?

It depends entirely on the setting. For mild, occasional wheeze in an adult the sponsor's trials report that it opens the airways and the measured systemic exposure is low. For anything beyond that it is contested: a 2023 editorial by respiratory specialists, cited separately in this entry, calls the evidence that it matches a modern selective reliever only low quality, and the hazard they name is someone treating worsening asthma with a reliever and no anti-inflammatory inhaler. The label's own alert is written around exactly that danger. (Source 3)

How do you get more of it?

It is bought over the counter in US pharmacies; there is no food or supplement route. The regulatory basis is the FDA's over-the-counter bronchodilator monograph, which lists epinephrine among the permitted active ingredients under a rule dated 2 October 1986. What the product actually delivers per spray and how often it may be used are set on the Drug Facts panel and are recorded under intakes, with the label as their source. (Source 25)

If it is harmful, what reduces it?

Inhaled epinephrine clears very fast on its own, which is one of the reasons systemic exposure stays low. In the crossover study, plasma levels after the inhaler returned to baseline in roughly 0.6 hour, compared with about 8 hours after an intramuscular injection and more than 24 hours for inhaled albuterol. So stopping use is what reduces it; no clearance treatment is described. (Source 15)

Why might someone be low in it or missing it?

This question does not really apply. Epinephrine is a hormone the body makes, so nobody is missing the molecule; what someone can lack is access to a reliever inhaler. The literature frames that as an access problem rather than a deficiency: the 2023 editorial argues for over-the-counter availability of a steroid-containing reliever particularly for disadvantaged populations, because the only over-the-counter option in the United States has been aerosolised epinephrine. (Source 17)

Which whole foods contain it or feed it?

None. No food contains it as a medicine and no food feeds it; it is a manufactured aerosol product. The opposite is true of the things the label tells people to keep away from while using it: caffeinated food and drink, and supplements with stimulant ingredients. (Source 5)

We searched: Europe PMC searches for inhaled epinephrine and dietary sources, plus the full Drug Facts label; no food source exists for an inhaled drug and none is described. The only food-related labelling is a caution about caffeine.

What happens if you do not have it?

Not using this particular inhaler is not a deficiency; most people with asthma use a prescribed reliever instead. What the literature does say is that going without any anti-inflammatory inhaler matters: a 2024 paper states that inhaled epinephrine used without an inhaled corticosteroid may increase the risk of asthma death, and a lifetime model estimated an absolute 0.23% higher risk of asthma-related death on inhaled epinephrine than on as-needed budesonide-formoterol. (Source 20)

How can you test for it?

There is no test for whether you are getting enough of it, and no routine blood test is used to monitor it. What the trials measured instead was lung function: the dose-ranging studies used spirometry for FEV1 before and after a dose. Plasma epinephrine can be measured, but the pharmacokinetic study had to separate the dose from the body's own endogenous epinephrine to do so, which is why that measurement is a research tool rather than a clinical test. (Source 2)

References

1. Journal of Aerosol Medicine and Pulmonary Drug Delivery. Comparison of Systemic Exposure Between Epinephrine Delivered via Metered-Dose Inhalation and Intramuscular Injection — Introduction, paragraph on professional criticism and guideline position. 2025. PMID 39207239, DOI 10.1089/jamp.2024.0025. Read the source
2. Journal of aerosol medicine and pulmonary drug delivery. A Dose-Ranging Study of Epinephrine Hydrofluroalkane Metered-Dose Inhaler (Primatene® MIST) in Subjects with Intermittent or Mild-to-Moderate Persistent Asthma — Results section of the abstract. 2020. PMID 32150492, DOI 10.1089/jamp.2019.1558. Read the source
3. DailyMed (US National Library of Medicine), SPL submitted by Armstrong Pharmaceuticals, Inc.; label version published 23 June 2026. Drug Facts label, Primatene MIST epinephrine inhalation aerosol — the "Warnings" section lead paragraph including the Asthma alert; the section's seven subsections are carried as separate references (prim-label-donotuse, -askdoctor, -askpharm, -whenusing, -stopuse, -pregnancy, -koorc). 2026. Read the source
4. DailyMed (US National Library of Medicine), SPL submitted by Armstrong Pharmaceuticals, Inc.; label version published 23 June 2026. Drug Facts label, Primatene MIST epinephrine inhalation aerosol — the complete "Do not use" section. 2026. Read the source
5. DailyMed (US National Library of Medicine), SPL submitted by Armstrong Pharmaceuticals, Inc.; label version published 23 June 2026. Drug Facts label, Primatene MIST epinephrine inhalation aerosol — the complete "When using this product" section. 2026. Read the source
6. DailyMed (US National Library of Medicine), SPL submitted by Armstrong Pharmaceuticals, Inc.; label version published 23 June 2026. Drug Facts label, Primatene MIST epinephrine inhalation aerosol — the complete "Ask a doctor or pharmacist before use if you are" section. 2026. Read the source
7. Annals of allergy, asthma & immunology : official publication of the American College of Allergy, Asthma, & Immunology. Cost-effectiveness of budesonide-formoterol vs inhaled epinephrine in US adults with mild asthma — Background section of the abstract. 2024. PMID 37879568, DOI 10.1016/j.anai.2023.10.024. Read the source
8. The Journal of asthma : official journal of the Association for the Care of Asthma. Long-term safety and efficacy studies of epinephrine HFA metered-dose inhaler (Primatene® Mist): a two-stage randomized controlled trial — Results section of the abstract. 2021. PMID 31959019, DOI 10.1080/02770903.2020.1713147. Read the source
9. DailyMed (US National Library of Medicine), SPL submitted by Armstrong Pharmaceuticals, Inc.; label version published 23 June 2026. Drug Facts label, Primatene MIST epinephrine inhalation aerosol — the complete "Stop use and ask a doctor if" section. 2026. Read the source
10. American Journal of Respiratory and Critical Care Medicine. Over-the-counter Dispensing: Widening Access to Inhaled Corticosteroid/Formoterol Reliever Therapy — seventh paragraph. 2023. PMID 36548806, DOI 10.1164/rccm.202212-2297ED. Read the source
11. Journal of Aerosol Medicine and Pulmonary Drug Delivery. A Dose-Ranging Study of Epinephrine Hydrofluroalkane Metered-Dose Inhaler (Primatene MIST) — Safety results, paragraph on total adverse events by treatment arm. 2020. PMID 32150492, DOI 10.1089/jamp.2019.1558. Read the source
12. Journal of Aerosol Medicine and Pulmonary Drug Delivery. A Dose-Ranging Study of Epinephrine Hydrofluroalkane Metered-Dose Inhaler (Primatene MIST) — Safety results, paragraph on the three most common adverse events. 2020. PMID 32150492, DOI 10.1089/jamp.2019.1558. Read the source
13. DailyMed (US National Library of Medicine); labeller Armstrong Pharmaceuticals, Inc.. Drug Facts label, Primatene MIST epinephrine inhalation aerosol — the complete pregnancy or breast-feeding subsection of Warnings (SPL section code 53414-9). 2026. Read the source
14. DailyMed (US National Library of Medicine); labeller Armstrong Pharmaceuticals, Inc.. Drug Facts label, Primatene MIST epinephrine inhalation aerosol — the complete keep-out-of-reach-of-children and overdose subsection of Warnings (SPL section code 50565-1). 2026. Read the source
15. Journal of aerosol medicine and pulmonary drug delivery. Comparison of Systemic Exposure Between Epinephrine Delivered via Metered-Dose Inhalation and Intramuscular Injection — Results section of the abstract. 2025. PMID 39207239, DOI 10.1089/jamp.2024.0025. Read the source
16. Journal of Aerosol Medicine and Pulmonary Drug Delivery. A Dose-Ranging Study of Epinephrine Hydrofluroalkane Metered-Dose Inhaler (Primatene MIST) — Discussion, limitations paragraph. 2020. PMID 32150492, DOI 10.1089/jamp.2019.1558. Read the source
17. American Journal of Respiratory and Critical Care Medicine. Over-the-counter Dispensing: Widening Access to Inhaled Corticosteroid/Formoterol Reliever Therapy — third paragraph. 2023. PMID 36548806, DOI 10.1164/rccm.202212-2297ED. Read the source
18. Journal of aerosol medicine and pulmonary drug delivery. Comparison of Systemic Exposure Between Epinephrine Delivered via Metered-Dose Inhalation and Intramuscular Injection — Author Disclosure Statement. 2025. PMID 39207239, DOI 10.1089/jamp.2024.0025. Read the source
19. Journal of aerosol medicine and pulmonary drug delivery. Comparison of Systemic Exposure Between Epinephrine Delivered via Metered-Dose Inhalation and Intramuscular Injection — Conclusion section of the abstract. 2025. PMID 39207239, DOI 10.1089/jamp.2024.0025. Read the source
20. Annals of allergy, asthma & immunology : official publication of the American College of Allergy, Asthma, & Immunology. Cost-effectiveness of budesonide-formoterol vs inhaled epinephrine in US adults with mild asthma — Results section of the abstract. 2024. PMID 37879568, DOI 10.1016/j.anai.2023.10.024. Read the source
21. DailyMed (US National Library of Medicine), SPL submitted by Armstrong Pharmaceuticals, Inc.; label version published 23 June 2026. Drug Facts label, Primatene MIST epinephrine inhalation aerosol — the complete "Directions" section. 2026. Read the source
22. Journal of aerosol medicine and pulmonary drug delivery. A Dose-Ranging Study of Epinephrine Hydrofluroalkane Metered-Dose Inhaler (Primatene® MIST) in Subjects with Intermittent or Mild-to-Moderate Persistent Asthma — Methods section of the abstract. 2020. PMID 32150492, DOI 10.1089/jamp.2019.1558. Read the source
23. The Journal of asthma : official journal of the Association for the Care of Asthma. Long-term safety and efficacy studies of epinephrine HFA metered-dose inhaler (Primatene® Mist): a two-stage randomized controlled trial — Method section of the abstract. 2021. PMID 31959019, DOI 10.1080/02770903.2020.1713147. Read the source
24. DailyMed (US National Library of Medicine), SPL submitted by Armstrong Pharmaceuticals, Inc.; label version published 23 June 2026. Drug Facts label, Primatene MIST epinephrine inhalation aerosol — the complete "Uses" section. 2026. Read the source
25. Code of Federal Regulations, US Government Publishing Office (govinfo). 21 CFR 341.16 Bronchodilator active ingredients (2024 annual revision). 2024. Read the source