A comparison of the efficacy and tolerability of single doses of HFA 134a albuterol and CFC albuterol in mild-to-moderate asthmatic patients.

Background: After the signing of the Montreal Protocol in 1987, new propellants for use in pressurized metered-dose inhalers that are non-ozone-depleting have been developed.

Objective: This study was designed to compare the efficacy and tolerability of single doses of albuterol/HFA 134a with albuterol/CFC and to demonstrate a dose-response among the different doses of both formulations.

Methods: A single-center, randomized, double-blind, placebo-controlled, cross-over study.