Tachyphylaxis following regular use of formoterol in exercise-induced bronchospasm.

Abstract

BACKGROUND:

Formoterol is a highly effective therapeutic agent in the prevention of exercise-induced bronchospasm (EIB). Regular use of beta-adrenergic drugs may result in a reduction in the protective effect afforded by these bronchodilators against bronchoconstrictor stimuli. It is unknown whether this effect extends to formoterol and exercise.

METHODS:

We performed a randomized, double-blind, parallel clinical trial in 19 patients with EIB. Each patient received inhaled formoterol or placebo twice daily during 4 weeks. Patients performed two exercise tests in a cycle ergometer on the 1st, 14th, and 28th study days separated 3 hours from each other. A dose of formoterol was given 30 min prior to the 2nd test.

RESULTS:

There were significant differences in bronchoprotection between days 1 and 14 (p = .012) and between days 1 and 28 (p = .012) in the formoterol group. No differences were found in the placebo group. The evolution of the bronchoprotection index was also significantly different between the formoterol and the placebo group (p = .002) from day 1 to 28.

CONCLUSIONS:

Tachyphylaxis developed to the protective effect of formoterol against EIB after 4 weeks of regular dosing. Tolerance was already found on day 14, though not progressive. Formoterol should be recommended only as needed in EIB.

• Authors: R García, P Guerra, F Feo, P A Galindo, E Gómez, J Borja, R Fernandez-Pacheco
• Journal: Journal of investigational allergology & clinical immunology (J Investig Allergol Clin Immunol) Vol. 11 Issue 3 Pg. 176-82 ( 2001) ISSN: 1018-9068 [Print] Spain
• PMID: 11831450 (Publication Type: Clinical Trial, Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)

Chemical References

• Adrenergic beta-Agonists
• Bronchodilator Agents
• Ethanolamines
• Formoterol Fumarate

Topics

• Adrenergic beta-Agonists (administration & dosage, adverse effects, therapeutic use)
• Adult
• Asthma, Exercise-Induced (drug therapy, physiopathology)
• Bronchodilator Agents (administration & dosage, adverse effects, therapeutic use)
• Double-Blind Method
• Ethanolamines (administration & dosage, adverse effects, therapeutic use)
• Exercise Test
• Female
• Forced Expiratory Volume (drug effects)
• Formoterol Fumarate
• Humans
• Male
• Tachyphylaxis
• Time Factors