Levalbuterol

What it is

Levalbuterol is one of the two mirror-image forms of albuterol (salbutamol). Ordinary albuterol is a 50:50 racemic mixture of (R)-albuterol and (S)-albuterol, and the (R) form is the one that opens the airways. Levalbuterol is that (R) form sold on its own, as a nebuliser solution and as a metered-dose inhaler. It was approved in the United States in 1999 and is an example of a "chiral switch": a single enantiomer marketed separately from an existing racemic drug.

What the research says

As a bronchodilator it works: in randomised trials against placebo it improved FEV1 in adults and in children. What is disputed is the marketing premise behind it. The claim was that removing (S)-albuterol would give better lung function with fewer heart and tremor side effects, and head-to-head trials have not borne that out; a meta-analysis of seven trials in acute asthma found no significant difference in any outcome or in side effects, and one paediatric trial of continuous nebulisation actually favoured racemic albuterol. Reviews of chiral-switch respiratory drugs call the therapeutic advantage "disappointing". The main harms are the class harms of short-acting beta2-agonists: tremor, palpitations, lowered blood potassium, rarely paradoxical bronchospasm, and, where the inhaler is relied on instead of anti-inflammatory treatment, higher rates of exacerbation and death.

Evidence grade: Well established.

How it works

Drug class: Short-acting selective beta2-adrenergic agonist (SABA); the single (R)-enantiomer of racemic albuterol (salbutamol)

Levalbuterol switches on beta2-adrenergic receptors on the muscle that rings the airways. That raises cyclic AMP inside those muscle cells, which makes them relax, so the airway widens within minutes and stays wider for about four to six hours. The same receptors exist in the heart and on skeletal muscle, which is why the drug can also raise heart rate, cause tremor and push potassium out of the blood into cells. (Source 1)

What it is used for

• Levalbuterol opens narrowed airways within minutes; randomised trials in adults and in children aged 4 to 11 showed significantly larger FEV1 improvements than placebo. What trials have not shown is any consistent advantage over ordinary racemic albuterol. Evidence: established. (Source 2)
• This is the premise levalbuterol was marketed on and it is not supported. A meta-analysis of seven acute-asthma trials found no significant difference in efficacy or side effects, a paediatric continuous-nebulisation trial favoured racemic albuterol, and chart reviews and a 2025 randomised trial found similar heart-rate and potassium effects. Evidence: disputed. (Source 3)
• Beta2-agonists drive potassium into cells and are used as a temporising measure in hyperkalaemia. A single-centre randomised trial compared levalbuterol with albuterol for this and found no difference in potassium lowering; this is one small trial, and no outcome trial supports levalbuterol specifically for this use. Evidence: limited. (Source 4)

Interactions

• Beta-blockers (including eye drops for glaucoma) (label): Beta-blockers block the airway effect of levalbuterol and can themselves trigger severe bronchospasm in people with asthma. (Source 5)
• Loop and thiazide diuretics (non-potassium-sparing) (label): Both lower blood potassium, so using them together can worsen hypokalaemia and the ECG changes that go with it, especially above the recommended dose. (Source 6)
• Digoxin (pharmacokinetic study): Albuterol lowered blood digoxin levels by about a sixth to a fifth in single-dose studies in healthy volunteers. The label says the clinical importance for people with airway disease is unclear, but that it is prudent to check digoxin levels in people taking both. (Source 6)
• Monoamine oxidase inhibitors and tricyclic antidepressants (label): These can amplify the cardiovascular effect of albuterol-type drugs; the label advises considering an alternative. (Source 5)
• Potassium (dietary, supplemental, or any medicine that moves potassium) (clinical trial): Levalbuterol itself lowers blood potassium by shifting it into cells. In a randomised paediatric trial every active beta2-agonist arm, levalbuterol included, dropped serum potassium against placebo. It is the direction of the drug's own effect that matters for anyone taking potassium supplements or potassium-lowering medicines, rather than a change in how either is absorbed. (Source 7)
• Other short-acting inhaled bronchodilators and adrenaline-type drugs (label): Using them at the same time adds to the cardiovascular effect; the label says they should not be used together. (Source 5)

Stopping it

• Levalbuterol is a reliever taken as needed and there is no documented withdrawal syndrome in the sources we read. The signal the label treats as important is the opposite one: needing it more often than usual is a marker that the asthma itself is destabilising and that anti-inflammatory treatment needs reviewing. (Source 8)
• The literature on stopping is about stopping reliever-only treatment rather than tapering the drug. A 2025 systematic review and meta-analysis found that using three or more SABA canisters a year was associated with roughly double the rate of death and exacerbations, which is why guidelines moved away from reliever-only asthma treatment. (Source 9)

What goes wrong

All active beta2-agonist treatments, including levalbuterol, lowered serum potassium compared with placebo in children, and levalbuterol 0.31 mg was the only arm that did not differ from placebo on heart rate, QTc and glucose. (Source 7)

• Randomized trial, Moderate certainty.
• Size: 338 children.
• Who: Children aged 4 to 11 years with persistent asthma.
• How long: 21 days.
• Result: Serum potassium fell by 0.3 to 0.6 (units as printed) on active treatment, P < .002 vs placebo; racemic albuterol 2.5 mg caused the greatest change, P < .005 vs other active arms.
• Funding: not stated in the record we read.

All active treatments decreased serum potassium (range, -0.3 to -0.6; P < .002 vs placebo), and RAC 2.5 mg caused the greatest change (P < .005 vs other actives).

Overuse of short-acting beta2-agonists, the class levalbuterol belongs to, is associated with roughly double the rate of death and of acute exacerbations in asthma. (Source 9)

• Meta-analysis, Low certainty.
• Size: 27 studies (2 RCTs, 1 prospective cohort, 12 retrospective cohorts, 12 cross-sectional); 130,629 overuse vs 300,451 control for mortality.
• Who: People with asthma dispensed three or more SABA canisters per year, 1981 to November 2023.
• How long: Varied by study.
• Result: Mortality 2,743/130,629 (2.1%) vs 3,534/300,451 (1.2%), RR 2.04 (95% CI 1.37-3.04), p < 0.001; acute exacerbations 60,320/165,271 vs 84,439/376,845, RR 1.93 (95% CI 1.24-3.03), p < 0.001.
• Funding: not stated in the record we read; mostly retrospective and cross-sectional data, so confounding by asthma severity cannot be excluded.

SABA overuse (≥ 3 SABA canisters/year) was associated with significantly higher mortality (2743 of 130,629 in the overuse group versus 3534 of 300,451 in controls; RR = 2.04, 95% confidence interval, CI = 1.37-3.04; p < 0.001)

The US prescribing information records that levalbuterol can cause paradoxical bronchospasm, which may be life-threatening. (Source 8)

• Official position, Certainty not rated.
• Size: Not applicable - regulatory position.
• Who: Adults, adolescents and children 4 years and older with reversible obstructive airway disease.
• How long: Position current as of SPL version 3, published 30 July 2025.
• Result: No rate given; the label records it as a warning rather than a measured frequency.
• Funding: Label held by Lupin Pharmaceuticals, Inc.

XOPENEX HFA can produce paradoxical bronchospasm, which may be life-threatening.

In the two 8-week registration trials, the adverse reactions more common with levalbuterol than placebo were respiratory and general rather than cardiac. (Source 10)

• Official position, Certainty not rated.
• Size: 748 adult and adolescent patients across two 8-week trials.
• Who: Adults and adolescents 12 years and older with asthma.
• How long: 8 weeks.
• Result: Reported in the label's table as levalbuterol 90 mcg vs racemic albuterol HFA 180 mcg vs placebo: asthma 9%/7%/6%, pharyngitis 8%/2%/2%, rhinitis 7%/2%/3%, dizziness 3%/1%/2%.
• Funding: Manufacturer-sponsored registration trials reported in the label.

Most common adverse reactions (≥ 2% and > placebo) are accidental injury, bronchitis, dizziness, pain, pharyngitis, rhinitis, and vomiting.

The US prescribing information warns that excessive use of levalbuterol may be fatal and that the recommended dose should not be exceeded. (Source 8)

• Official position, Certainty not rated.
• Size: Not applicable - regulatory position.
• Who: Adults, adolescents and children 4 years and older with reversible obstructive airway disease.
• How long: Position current as of SPL version 3, published 30 July 2025.
• Result: No rate given; the label records it as a warning rather than a measured frequency.
• Funding: Label held by Lupin Pharmaceuticals, Inc.

Excessive use may be fatal. Do not exceed recommended dose.

What the evidence supports

In a 4-week randomised placebo-controlled trial in moderate-to-severe asthma, levalbuterol produced a larger first-dose peak FEV1 response than an equivalent amount of levalbuterol given as racemic albuterol, but the difference was no longer significant after 4 weeks. (Source 2)

• Randomized trial, Moderate certainty.
• Size: 362 patients.
• Who: Patients aged 12 years and older with moderate-to-severe asthma.
• How long: 28 days, nebulised three times daily.
• Result: Peak FEV1 change to first dose 0.92 L (combined levalbuterol) vs 0.82 L (combined racemic albuterol), P=.03; after 4 weeks 0.84 L vs 0.74 L, not significant.
• Funding: not stated in the record we read.

The change in peak FEV1 response to the first dose in the combined levalbuterol group was significantly greater compared with the combined racemic albuterol group (0.92 and 0.82 L, respectively; P =.03), with similar but nonsignificant results after 4 weeks (0.84 and 0.74 L, respectively).

In children with asthma, nebulised levalbuterol at 0.31 mg and 0.63 mg improved FEV1 significantly more than placebo, as did racemic albuterol. (Source 7)

• Randomized trial, Moderate certainty.
• Size: 338 children.
• Who: Children aged 4 to 11 years with FEV1 40% to 85% of predicted.
• How long: 21 days, three times daily.
• Result: Median peak percent change in FEV1 2.0% (placebo), 19.0% (levalbuterol 0.31 mg), 18.1% (levalbuterol 0.63 mg), 12.4% (racemic 1.25 mg), 15.6% (racemic 2.5 mg); P < .05 vs placebo.
• Funding: not stated in the record we read.

All active treatments significantly improved the primary endpoint in comparison with placebo (P < .001).

What the evidence does not support

A systematic review and meta-analysis of seven randomised trials in acute asthma found no significant difference between levalbuterol and racemic albuterol on any efficacy outcome or in side effects. (Source 3)

• Meta-analysis, Low certainty.
• Size: 1,625 participants across 7 trials.
• Who: All age groups presenting with acute asthma.
• How long: Acute treatment episodes.
• Result: Mean difference (95% CI): respiratory rate 0.35 (-0.81, 1.51); oxygen saturation -0.29 (-0.68, 0.10); percentage change in FEV1 -28.3 (-59.95, 3.33); clinical asthma score -1.01 (-5.30, 3.28)
• Funding: not stated in the record we read; the review notes missing data for two probably eligible trials and that assumptions and calculated values were used.

Respiratory rate, oxygen saturation, and percentage change in FEV1 and clinical asthma score were not significantly different between the groups with mean difference (95% CI) of 0.35 (-0.81, 1.51), -0.29 (-0.68, 0.10), -28.3 (-59.95, 3.33) and -1.01 (-5.30, 3.28) respectively.

The same meta-analysis concluded that levalbuterol should not be used in preference to racemic albuterol for acute asthma. (Source 3)

• Meta-analysis, Low certainty.
• Size: 1,625 participants across 7 trials.
• Who: All age groups with acute asthma.
• How long: Acute treatment episodes.
• Result: No significant difference in efficacy or safety outcomes.
• Funding: not stated in the record we read.

Levalbuterol was not superior to albuterol regarding efficacy and safety in subjects with acute asthma. We suggest that levalbuterol should not be used over albuterol for acute asthma.

In a double-blind trial of continuous nebulisation for acute paediatric asthma, racemic albuterol gave better lung function and asthma scores than levalbuterol at the doses used. (Source 11)

• Randomized trial, Low certainty.
• Size: 99 children completed.
• Who: Children aged 6 to 17 with acute asthma exacerbation and initial FEV1 below 70% predicted in an emergency department.
• How long: One to two hours of continuous nebulisation.
• Result: Greater improvement in FEV1 with racemic albuterol (p = .043) and in asthma score (p = .01) at 1 hour; asthma score advantage maintained at 2 hours (p = .008); no difference in heart rate, respiratory rate, oxygen saturation or admission rates.
• Funding: not stated in the record we read.

Children in the RAC group had a greater improvement in their FEV1 (p = .043) as well as in their asthma scores (p = .01) after 1 hour of continuous treatment compared to the LEV group.

A randomised trial in people with hyperkalaemia found no difference between levalbuterol and albuterol in heart-rate change or in potassium lowering. (Source 4)

• Randomized trial, Low certainty.
• Size: single-centre randomised trial (NCT05173584); group sizes not given in the record we read.
• Who: Hyperkalaemic patients at Aleppo University Hospital, Syria.
• How long: 90 minutes of observation.
• Result: No significant difference in mean heart-rate change at 30 minutes or in serum potassium change at 90 minutes; tremor and nervousness most commonly reported in both arms.
• Funding: not stated in the record we read.

The results showed no significant difference in mean HR change between Levalbuterol and Albuterol groups at 30 min, nor in the change in potassium serum levels at 90 min.

A retrospective chart review in hospitalised children found levalbuterol and racemic albuterol produced similar heart-rate changes, even though the racemic doses were larger. (Source 12)

• Cohort study, Very low certainty.
• Size: 50 children (25 per group)
• Who: Hospitalised children aged 1 month to 12 years given three consecutive nebulised doses.
• How long: Three consecutive doses.
• Result: Median largest percentage change in heart rate 4.1% (IQR 1.8-8.7) with levalbuterol vs 5% (IQR 1.9-7.8) with racemic albuterol, p = 0.763; more than 10% heart-rate rise in 4 vs 5 patients, p = 1.0.
• Funding: not stated in the record we read.

The median of the largest percentage of change in HR was 4.1% (interquartile range [IQR], 1.8-8.7) in the levalbuterol group compared to 5% (IQR, 1.9-7.8) in the racemic albuterol group (p = 0.763).

A review of chiral-switch respiratory drugs judged the therapeutic advantage of levalbuterol and similar single-enantiomer drugs over their racemates to have been disappointing. (Source 13)

• Expert review, not systematic, Very low certainty.
• Size: Not stated - expert summary with no stated search method.
• Who: Respiratory and allergy single-enantiomer drugs including levalbuterol, arformoterol and levocetirizine.
• How long: Not applicable.
• Result: No pooled estimate; the review also notes single-enantiomer drugs may be several-fold more expensive than the racemate.
• Funding: not stated in the record we read.

However, the therapeutic advantages of single enantiomer drugs developed for respiratory use such as levalbuterol, arformoterol, and levocetirizine over their racemate has been disappointing.

A review of randomised trials found no clear advantage for levalbuterol over racemic albuterol in intensive care populations and no trials at all in patients with underlying tachyarrhythmia. (Source 14)

• Systematic review, Very low certainty.
• Size: Randomised controlled trials identified by a PubMed MeSH search; number not given in the record we read.
• Who: Patients with respiratory disease, with attention to those with tachyarrhythmias.
• How long: Varied.
• Result: No pooled estimate reported; the review states evidence in tachyarrhythmia is lacking and insufficient.
• Funding: not stated in the record we read.

Randomized controlled trials show that in intensive care unit patient populations there is no clear advantage to using levalbuterol over albuterol; however, this did not hold true in pediatric populations.

Where the evidence is mixed

In a Medicaid claims cohort, children whose prescriptions were filled for levalbuterol had fewer asthma-related emergency department visits than those filled for albuterol, but no difference in hospitalisations; this is an association in dispensing records, not a randomised comparison. (Source 15)

• Cohort study, Very low certainty.
• Size: 8,172 children aged 2-18 years.
• Who: Asthmatic children with pharmacy refills in the South Carolina Medicaid database, 2002-2011, propensity-score matched.
• How long: 12-month follow-up.
• Result: Asthma-related ED visits 8.76% (levalbuterol) vs 14.21% (albuterol); adjusted incidence rate ratio 0.57 (95% CI 0.49-0.65); hospitalisations 1.07% vs 1.12%, IRR 0.93 (95% CI 0.99-1.63 as printed)
• Funding: grants listed as ASPIRE-I, ASPIRE-III and Social Sciences in the record we read.

Comparing the levalbuterol group to the albuterol group, the adjusted IRR estimate was 0.57 (95% confidence interval [CI], 0.49-0.65) for of asthma-related ED visits, and 0.93 (95%CI, 0.99-1.63) for hospitalizations.

Measured plasma concentrations of both albuterol enantiomers in emergency-department patients were high and variable but were not associated with better lung function or with QTc prolongation. (Source 16)

• Blood level study, Very low certainty.
• Size: Observational sample of emergency-department patients; number not given in the record we read.
• Who: Adults presenting with acute severe asthma or COPD.
• How long: Single presentation.
• Result: Median (range) plasma concentrations in acute asthma 8.2 (0.6-24.8) ng/mL for (R)-albuterol and 20.6 (0.5-57.3) ng/mL for (S)-albuterol; in COPD 2.1 (0.0-16.7) and 4.1 (0.0-36.1) ng/mL.
• Funding: not stated in the record we read.

High plasma concentrations of albuterol were observed in both asthma and COPD patients presenting to the emergency department.

Where the research disagrees

Whether the single (R)-enantiomer is better than ordinary racemic albuterol

• Nelson and colleagues, in the trial that supported approval, A 362-patient randomised double-blind placebo-controlled trial of nebulised drug over 28 days: Levalbuterol appears to provide a better therapeutic index than the standard dose of racemic albuterol. These results support the concept that (S)-albuterol may have detrimental effects on pulmonary function. (Source 17)
• Jat and Khairwa, pooling the head-to-head trials, Systematic review and meta-analysis of seven randomised trials, 1,625 participants: Levalbuterol was not superior to albuterol regarding efficacy and safety in subjects with acute asthma. (Source 3)
• A review of chiral-switch respiratory drugs, Narrative review with no stated search method: the therapeutic advantages of single enantiomer drugs developed for respiratory use such as levalbuterol, arformoterol, and levocetirizine over their racemate has been disappointing (Source 13)

How much

• Reference intake: There is no reference intake for a prescription bronchodilator; the dose is set by the prescriber. As a position, the US prescribing information for the Xopenex HFA inhaler (SPL version 3, 30 July 2025) states the recommended dosage for adults and children 4 years and older as 2 inhalations, 90 mcg of levalbuterol free base, every 4 to 6 hours, with 1 inhalation (45 mcg) every 4 hours sufficient for some. (Source 18)
• Upper limit: No tolerable upper intake level exists for a prescription drug. As a position, the same label states that excessive use may be fatal and that the recommended dose should not be exceeded. (Source 8)
• Studied: Nebulised levalbuterol 0.63 mg and 1.25 mg three times daily for 28 days, against racemic albuterol 1.25 mg and 2.5 mg and placebo, in 362 patients aged 12 and over. (Source 2)
• Studied: Nebulised levalbuterol 0.31 mg and 0.63 mg three times daily for 21 days, against racemic albuterol 1.25 mg and 2.5 mg and placebo, in 338 children aged 4 to 11. (Source 7)
• Studied: Continuous nebulisation of levalbuterol 3.75 mg over one hour against racemic albuterol 7.5 mg over one hour in children aged 6 to 17 in an emergency department. (Source 11)

A common belief, and what the research shows

The belief: Levalbuterol is the heart-safe version of albuterol, so it is the one to use if you get palpitations or tremor.

What the research shows: Head-to-head evidence does not support that. The pooled analysis of acute-asthma trials reported that "There were no significant differences in side effects between groups." A chart review in children found the median largest heart-rate change was 4.1% with levalbuterol and 5% with racemic albuterol (p = 0.763), despite larger racemic doses, and a 2025 randomised trial found no difference in heart-rate change or potassium lowering. Levalbuterol still lowers potassium and can still raise heart rate: in children "All active treatments decreased serum potassium (range, -0.3 to -0.6; P < .002 vs placebo)".

Questions and answers

What is it?

Levalbuterol is one half of albuterol. Ordinary albuterol is an equal mixture of two mirror-image molecules, and only the (R) form opens the airways; levalbuterol is that (R) form sold on its own, as a nebuliser solution or a puffer. It is a prescription short-acting beta2-agonist, the same class as albuterol. (Source 2)

What does it do in the body?

It switches on beta2 receptors on the muscle around the airways, which raises cyclic AMP inside those cells and makes the muscle relax, so the airway widens. The effect starts within minutes and the label dosing interval is every 4 to 6 hours. Because beta2 receptors also sit in the heart and on skeletal muscle, the same drug can raise heart rate, cause tremor and lower blood potassium. (Source 1)

Is it good or bad for you?

Good as a rescue treatment for an attack of airway narrowing, where randomised trials show clear FEV1 gains over placebo. Not better than ordinary albuterol: the pooled head-to-head trials found no difference in efficacy or side effects, so the extra cost buys nothing measurable. It becomes harmful when it replaces anti-inflammatory treatment; needing three or more canisters a year was associated with roughly double the rate of death and exacerbations in a 2025 meta-analysis. (Source 3)

How do you get more of it?

Only on prescription, as a nebuliser solution or a metered-dose inhaler. There is no food, supplement or behaviour that provides it; it is a manufactured drug, not a nutrient. The prescribing information frames the amount entirely as a prescriber decision, and the label dose for the inhaler in adults and children aged 4 and over is 2 inhalations every 4 to 6 hours. (Source 18)

If it is harmful, what reduces it?

Nothing is needed to clear it in the usual sense: the airway effect fades over about 4 to 6 hours and the drug is cleared by the body. If it causes harm the response in the label is to stop it, immediately in the case of paradoxical bronchospasm or an immediate hypersensitivity reaction, and to consider stopping it if cardiovascular effects appear. A beta-blocker would block its airway effect but is not used for that purpose, because it can itself trigger severe bronchospasm. (Source 8)

Why might someone be low in it or missing it?

Levalbuterol is not something a person can be deficient in, so "missing" means not having a reliever available or not using it when needed. The clinically important pattern in the literature is the reverse of missing it: relying on a short-acting beta2-agonist instead of inhaled anti-inflammatory treatment. Needing more doses than usual is treated in the label as a sign that the asthma is destabilising. (Source 8)

Which whole foods contain it or feed it?

None. No whole food contains levalbuterol or provides a precursor to it, and we found no documented food interaction in the trials, reviews or prescribing information we read. The label's interaction section lists only medicines: other short-acting bronchodilators and adrenaline-type drugs, beta-blockers, non-potassium-sparing diuretics, digoxin, and MAO inhibitors or tricyclic antidepressants. (Source 5)

We searched: Europe PMC searches for levalbuterol with food, diet, caffeine and alcohol terms, plus the full drug interactions and clinical pharmacology sections of the Xopenex HFA prescribing information; nothing on food or alcohol was found.

What happens if you do not have it?

Without a reliever, bronchospasm goes untreated, which is what the drug is licensed to treat or prevent. There is no deficiency state. A reliever alone is also not enough for most people with asthma: the label itself says a beta-agonist on its own may not control asthma and that anti-inflammatory treatment should be considered early. (Source 8)

How can you test for it?

There is no blood test used in practice to check a levalbuterol level. What is measured is the response: trials used FEV1 by spirometry as the primary endpoint, and that is also how reversibility is assessed clinically. Plasma assays for the (R) and (S) enantiomers exist in research settings, and in one emergency-department study the measured levels varied widely and were not associated with lung-function improvement or with QTc prolongation, so a blood level would not be informative. (Source 16)

References

1. DailyMed / US FDA Structured Product Label, Lupin Pharmaceuticals, Inc.. XOPENEX HFA (levalbuterol tartrate) inhalation aerosol - full prescribing information (SPL version 3, published 30 July 2025) - section 12.1 Mechanism of Action. 2025. Read the source
2. The Journal of Allergy and Clinical Immunology. Improved bronchodilation with levalbuterol compared with racemic albuterol in patients with asthma. 1998. PMID 9847435, DOI 10.1016/s0091-6749(98)70332-x. Read the source
3. Pulmonary Pharmacology & Therapeutics. Levalbuterol versus albuterol for acute asthma: a systematic review and meta-analysis. 2013. PMID 23207739, DOI 10.1016/j.pupt.2012.11.003. Read the source
4. Frontiers in Cardiovascular Medicine. Assessing the cardiovascular and potassium lowering effects of levalbuterol compared to albuterol: a randomized control trial. 2025. PMID 41437987, DOI 10.3389/fcvm.2025.1463999. Read the source
5. DailyMed / US FDA Structured Product Label, Lupin Pharmaceuticals, Inc.. XOPENEX HFA (levalbuterol tartrate) inhalation aerosol - full prescribing information (SPL version 3, published 30 July 2025) - section 7 Drug Interactions and section 7.1 Beta-blockers. 2025. Read the source
6. DailyMed / US FDA Structured Product Label, Lupin Pharmaceuticals, Inc.. XOPENEX HFA (levalbuterol tartrate) inhalation aerosol - full prescribing information (SPL version 3, published 30 July 2025) - sections 7.2 and 7.3 Diuretics and Digoxin. 2025. Read the source
7. The Journal of Allergy and Clinical Immunology. Low-dose levalbuterol in children with asthma: safety and efficacy in comparison with placebo and racemic albuterol. 2001. PMID 11742271, DOI 10.1067/mai.2001.120134. Read the source
8. DailyMed / US FDA Structured Product Label, Lupin Pharmaceuticals, Inc.. XOPENEX HFA (levalbuterol tartrate) inhalation aerosol - full prescribing information (SPL version 3, published 30 July 2025) - section 5 Warnings and Precautions. 2025. Read the source
9. Allergy. Adverse Outcomes Associated With Short-Acting Beta-Agonist Overuse in Asthma: A Systematic Review and Meta-Analysis. 2025. PMID 40491263, DOI 10.1111/all.16538. Read the source
10. DailyMed / US FDA Structured Product Label, Lupin Pharmaceuticals, Inc.. XOPENEX HFA (levalbuterol tartrate) inhalation aerosol - full prescribing information (SPL version 3, published 30 July 2025) - section 6 Adverse Reactions. 2025. Read the source
11. The Journal of Asthma. Efficacy of racemic albuterol versus levalbuterol used as a continuous nebulization for the treatment of acute asthma exacerbations: a randomized, double-blind, clinical trial. 2011. PMID 21275850, DOI 10.3109/02770903.2011.554939. Read the source
12. The Journal of Pediatric Pharmacology and Therapeutics. Comparison of levalbuterol and racemic albuterol based on cardiac adverse effects in children. 2011. PMID 22479161, DOI 10.5863/1551-6776-16.3.191. Read the source
13. Pediatric Allergy, Immunology, and Pulmonology. Chiral Switch Drugs for Asthma and Allergies: True Benefit or Marketing Hype. 2013. PMID 24066264, DOI 10.1089/ped.2013.0285. Read the source
14. The Journal of Pharmacy Technology. Safety of Levalbuterol Compared to Albuterol in Patients With a Tachyarrhythmia. 2014. PMID 34860877, DOI 10.1177/8755122513507700. Read the source
15. Pediatric Pulmonology. Clinical outcomes of levalbuterol versus racemic albuterol in pediatric patients with asthma: Propensity score matching approach in a medicaid population. 2017. PMID 27701831, DOI 10.1002/ppul.23565. Read the source
16. International Journal of Emergency Medicine. Albuterol enantiomer levels, lung function and QTc interval in patients with acute severe asthma and COPD in the emergency department. 2011. PMID 21676212, DOI 10.1186/1865-1380-4-30. Read the source
17. The Journal of Allergy and Clinical Immunology. Improved bronchodilation with levalbuterol compared with racemic albuterol in patients with asthma - conclusion. 1998. PMID 9847435, DOI 10.1016/s0091-6749(98)70332-x. Read the source
18. DailyMed / US FDA Structured Product Label, Lupin Pharmaceuticals, Inc.. XOPENEX HFA (levalbuterol tartrate) inhalation aerosol - full prescribing information (SPL version 3, published 30 July 2025) - section 2.1 Recommended Dosages. 2025. Read the source