After an acute asthma exacerbation in a teenager or adult, should I discharge the patient with a short‑acting β2‑agonist (SABA) rescue inhaler or can I send them home with formoterol alone?

Discharge Rescue Therapy After Acute Asthma Exacerbation

You can discharge patients home on ICS/formoterol alone without a separate SABA, but only if the patient is on GINA steps 3–4 (moderate asthma requiring daily ICS/LABA maintenance therapy) and you prescribe formoterol-containing products specifically—never salmeterol-containing combinations. 1

Clinical Context and Rationale

After an acute asthma exacerbation, the choice of rescue therapy depends on the patient's baseline asthma severity and maintenance regimen:

For Patients on Steps 3–4 (Moderate Asthma)

• ICS/formoterol can serve as both maintenance and reliever therapy in the SMART (Single Maintenance And Reliever Therapy) regimen, eliminating the need for a separate SABA inhaler. 1
• Formoterol has a rapid onset of bronchodilation (≈1 minute, comparable to albuterol at 5 minutes), making it suitable for acute symptom relief. 2, 3
• This approach reduces exacerbations requiring oral corticosteroids compared to SABA-only rescue therapy (101 vs 117 per 1000 patients over 30 weeks). 4
• The NAEPP 2020 guidelines specifically recommend SMART for steps 3 and 4 in both children ≥12 years and adults. 1

For Patients on Step 5 or Higher (Severe Asthma)

• Discharge with a SABA (albuterol) as the rescue inhaler because high-quality evidence for ICS/formoterol reliever therapy at step 5 does not exist. 1
• The NAEPP working group did not recommend ICS/formoterol reliever therapy at step 5 due to lack of evidence, though GINA guidelines differ on this point. 1
• If the patient strongly prefers ICS/formoterol and has demonstrated benefit, you may continue it through shared decision-making, but this represents off-label use without robust trial data. 1

For Patients on Steps 1–2 (Mild or Intermittent Asthma)

• Discharge with albuterol as the primary rescue therapy, though ICS/formoterol reliever therapy is emerging as an alternative. 1, 5
• ICS/formoterol at step 2 is as effective as daily ICS for reducing exacerbations but may be inferior for symptom control. 1
• GINA 2019 recommends ICS/formoterol for adults with intermittent asthma, but NAEPP does not endorse this approach, creating guideline divergence. 1

Critical Product Selection Rules

Formoterol-Based Products Only for SMART

• Only formoterol-containing combinations (budesonide/formoterol, mometasone/formoterol) can be used for reliever therapy because formoterol has rapid onset (median 11.7 minutes to 15% FEV₁ increase). 1, 2, 3
• Never use salmeterol-containing products (fluticasone/salmeterol) as rescue therapy because salmeterol has delayed onset and is unsuitable for acute symptom relief. 1, 2

Evidence Base and Alternatives

• Most SMART trials used budesonide/formoterol, but the NAEPP working group designated "ICS/formoterol" (not "budesonide/formoterol"), allowing mometasone/formoterol or other ICS/formoterol combinations. 1
• If insurance covers only one canister, you may theoretically prescribe one ICS/LABA for maintenance and a separate formoterol-only inhaler for rescue, though this strategy has never been formally studied. 1

Practical Discharge Algorithm

Step 1: Determine Baseline Asthma Severity

• Steps 3–4 (moderate asthma on daily ICS/LABA): Discharge with ICS/formoterol for both maintenance and rescue (SMART regimen). 1
• Step 5 or higher (severe asthma): Discharge with albuterol as rescue therapy. 1
• Steps 1–2 (mild/intermittent asthma): Discharge with albuterol as rescue therapy (preferred by NAEPP). 1

Step 2: Prescribe Appropriate Rescue Therapy

• If using ICS/formoterol as rescue: Prescribe up to 8 puffs per day for ages 5–11 years or up to 10 puffs per day for ages ≥12 years. 1
• If using albuterol as rescue: Prescribe 2 puffs (200 µg each) every 4–6 hours as needed. 6

Step 3: Patient Education

• Patients must clearly understand which inhaler serves as the reliever to avoid confusion when multiple products are prescribed. 1
• Overuse of rescue therapy (>2 days per week, excluding exercise-related use) signals poor asthma control and warrants escalation of controller therapy. 6

Common Pitfalls and Caveats

Regulatory and Safety Considerations

• SMART remains off-label use in the United States, even after the boxed warning for asthma-related death was removed from ICS/LABA labels. 1, 2
• SMART should not be used in children younger than 12 years per NAEPP guidelines. 2
• The total daily dose of formoterol must not exceed 24 µg (approximately five inhalations of a 160/4.5 µg strength inhaler). 2

Insurance and Reimbursement Issues

• Some insurers will not pay for two canisters of the same ICS/LABA at once, which is required for SMART. 1
• This reimbursement barrier may improve over time with adoption of the NAEPP update. 1

Guideline Divergence

• GINA recommends ICS/formoterol reliever therapy at step 5 and for intermittent asthma in adults, while NAEPP does not. 1
• Clinicians should weigh the relatively modest benefits of formoterol as-needed against the benefits of single-inhaler therapy and the potential danger of long-term LABA use in some patients. 4

Discharge Medications Beyond Rescue Therapy

• All patients should be discharged on prednisolone 30 mg daily or more for 1–3 weeks, inhaled steroids at higher dosage than before admission, and inhaled/nebulized β-agonists for use as necessary. 1
• Patients should not be discharged until peak expiratory flow is above 75% of predicted value or their best level, with diurnal variability below 25% and no nocturnal symptoms. 1