What is the equivalent dose of fluticasone-salmeterol (Fluticasone (corticosteroid) and Salmeterol (long-acting beta2-adrenergic receptor agonist (LABA))) when switching from Dulera (Formoterol (LABA) and Mometasone (corticosteroid)) 200-5 mcg?

Equivalent Dosing When Switching from Dulera 200-5 mcg to Fluticasone-Salmeterol

When switching from Dulera (mometasone/formoterol) 200-5 mcg to fluticasone-salmeterol, the equivalent dose is fluticasone-salmeterol 250/50 mcg twice daily.

Rationale for Dose Equivalence

The conversion between these two combination inhalers requires understanding the relative potencies of both the corticosteroid and LABA components:

1. Corticosteroid Component:

   • Dulera contains mometasone 200 mcg per actuation
   • The equivalent fluticasone dose is 250 mcg based on relative potency 1
   • This is supported by clinical guidelines that categorize both mometasone 200 mcg and fluticasone 250 mcg as medium-dose ICS 2

2. LABA Component:

   • Dulera contains formoterol 5 mcg per actuation
   • Fluticasone-salmeterol contains salmeterol 50 mcg per actuation
   • Both formoterol and salmeterol are long-acting beta2-agonists with approximately 12-hour duration of action 1

Clinical Considerations

Pharmacological Differences

While both combinations provide similar clinical outcomes, there are some differences to be aware of:

• Onset of action: Formoterol (in Dulera) has a more rapid onset of bronchodilator action compared to salmeterol, which requires 15-30 minutes to take effect 1
• Potency: The corticosteroid components (mometasone and fluticasone) have different potencies by weight, but the recommended doses provide comparable anti-inflammatory effects 2

Efficacy Considerations

Studies comparing these combinations have shown:

• Both combinations effectively control asthma symptoms and reduce exacerbations 3
• A therapeutic interchange study showed that switching from fluticasone/salmeterol to mometasone/formoterol actually resulted in a statistically significant decrease in COPD exacerbations (34.2% vs 28.6%, p=0.030) 3
• Both combinations have demonstrated improvements in lung function, symptom control, and quality of life compared to monotherapy with corticosteroids alone 4, 5, 6

Safety Profile

Both combinations have similar safety profiles:

• The most common adverse events include headache, throat irritation, hoarseness, and oral candidiasis 5
• Neither combination should be used as monotherapy for asthma due to safety concerns with LABAs 1, 7
• Both should be administered twice daily for optimal effect 2

Important Clinical Pitfalls to Avoid

1. Never use LABAs as monotherapy: LABAs should never be used alone for asthma management due to increased risk of asthma-related death 1, 7

2. Avoid abrupt discontinuation: When switching between these medications, ensure continuous coverage to prevent loss of asthma control

3. Consider tolerance development: Regular use of LABAs can lead to tolerance, manifested as reduced duration and magnitude of protection against exercise-induced bronchoconstriction 1

4. Patient education is crucial: Ensure patients understand proper inhaler technique with the new device, as this significantly impacts medication effectiveness 2

5. Monitor for adequate control: Schedule follow-up within 2-6 weeks after switching to assess response and ensure adequate symptom control 2

In conclusion, when converting from Dulera 200-5 mcg to fluticasone-salmeterol, the appropriate equivalent dose is fluticasone-salmeterol 250/50 mcg administered twice daily. This provides comparable control of both the inflammatory and bronchoconstrictive components of asthma.