Which property of formoterol, unlike salmeterol, allows it to be used both as maintenance therapy and as a reliever medication in single-inhaler combination regimens with budesonide?

• A Longer duration of action than salmeterol
• B Resistance to COMT metabolism
• C Absence of beta-2 selectivity
• D Rapid onset of bronchodilation comparable to salbutamol ✓

Explanation

Formoterol is a full beta-2 agonist with a lipophilicity profile that gives it both a rapid onset (within 1 to 3 minutes, similar to salbutamol) and a long duration of about 12 hours. This dual profile underpins MART or SMART regimens where the same budesonide-formoterol inhaler serves maintenance and relief. Salmeterol has a slower onset of 15 to 30 minutes due to its exosite binding, making it unsuitable for rescue use.

Reference: Katzung's Basic and Clinical Pharmacology, 16th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.