What is the correct dosing of XOPENEX (levalbuterol) for children and adults?

Xopenex (Levalbuterol) Dosing

For adults and children ≥4 years with asthma, dose Xopenex HFA MDI as 2 inhalations (90 mcg) every 4-6 hours for routine bronchodilation; for acute exacerbations, use nebulized levalbuterol 0.075 mg/kg (minimum 1.25 mg) in children or 1.25-2.5 mg in adults every 20 minutes for 3 doses, then 0.075-0.15 mg/kg (up to 5 mg) every 1-4 hours as needed. 1, 2

Formulation-Specific Dosing

MDI (Metered-Dose Inhaler) - 45 mcg/puff

• Adults and children ≥4 years: 2 inhalations (90 mcg total) every 4-6 hours 2
• Some patients may respond adequately to 1 inhalation every 4 hours 2
• Acute exacerbations: Follow the same dosing as albuterol MDI (4-8 puffs every 20 minutes for 3 doses, then every 1-4 hours as needed) 1
• Prime with 4 test sprays before first use or if unused for >3 days 2

Nebulizer Solution (0.63 mg/3 mL, 1.25 mg/3 mL)

For Acute Exacerbations:

• Children:

  • 0.075 mg/kg (minimum dose 1.25 mg) every 20 minutes for 3 doses 1, 3
  • Then 0.075-0.15 mg/kg (up to 5 mg) every 1-4 hours as needed 1, 3

• Adults:

  • 1.25-2.5 mg every 20 minutes for 3 doses 1, 3
  • Then 1.25-5 mg every 1-4 hours as needed 1, 3

For Routine Maintenance (ages 2-11 years):

• Ages 2-5 years: 0.31 mg or 0.63 mg three times daily 4
• Ages 4-11 years: 0.31-1.25 mg three times daily 1, 5
  • Start with 0.31 mg in children with mild-moderate asthma 5
  • Higher doses (0.63 mg) may benefit those with severe disease 5

Key Dosing Principles

Levalbuterol is administered at half the milligram dose of racemic albuterol to provide comparable efficacy and safety. 1 This is because levalbuterol contains only the therapeutically active (R)-enantiomer, while racemic albuterol is 50% active (R)-enantiomer and 50% inactive (S)-enantiomer.

Dose Equivalency

• Levalbuterol 0.63 mg ≈ Albuterol 1.25 mg
• Levalbuterol 1.25 mg ≈ Albuterol 2.5 mg
• Levalbuterol MDI 45 mcg/puff ≈ Albuterol MDI 90 mcg/puff

Clinical Context

When to Escalate Dosing

If a previously effective regimen fails to provide the usual response, this signals asthma destabilization requiring reevaluation and consideration of anti-inflammatory therapy (e.g., corticosteroids) 2. More frequent administration or larger numbers of inhalations are not routinely recommended 2.

Nebulizer Administration Details

• Dilute aerosols to minimum of 3 mL at gas flow of 6-8 L/min 1, 3
• May mix with ipratropium nebulizer solution 1, 3
• Has not been evaluated for continuous nebulization 1—this is a critical limitation compared to albuterol

Special Populations

• Renal impairment: Use caution with high doses; renal disease causes 67% decline in albuterol clearance 2
• Children <4 years: Xopenex HFA MDI is not FDA-approved for this age group 2
• Ages 2-5 years: Only nebulizer solution has been studied 4

Important Caveats

Levalbuterol offers no clear clinical superiority over racemic albuterol despite theoretical advantages. A 2013 meta-analysis of 1625 patients found no significant differences in FEV₁ improvement, respiratory rate, oxygen saturation, or side effects between levalbuterol and albuterol 6. The 2008 hospitalized patient study showed levalbuterol required fewer total nebulizations (10 vs 12, p=0.031) but similar clinical outcomes and costs 7. However, a 2015 study found levalbuterol resulted in longer hospital stays (8.5 vs 6.8 days) and higher costs ($8003 vs $5772) without clinical benefit 8.

The primary advantage is reduced beta-mediated side effects at equivalent therapeutic doses, particularly relevant in children where levalbuterol 0.31 mg was the only treatment not different from placebo for heart rate and QTc changes 5.