Effect of solution and suspension type aerosol of formoterol on tremor response and airways in patients with asthma.
BACKGROUND
Aerosol delivery and deposition to the oropharynx and the lungs have been found to be different for solution-type and suspension-type metered-dose aerosols used for treatment of asthma. We investigated possible differences in clinical effects between solution and suspension metered-dose formoterol aerosols.


METHODS
A total of 24 patients with asthma (forced expiratory volume in 1 second, < or = 70% predicted) inhaled single doses (12 micrograms or 24 micrograms) of formoterol solution and suspension so that we could investigate the immediate tremor, airway, and cardiovascular responses in a randomized, double-blind, crossover trial. Fenoterol suspension aerosol (400 micrograms) was used for comparison (single-blind, poststudy, nonrandomized administration). Fenoterol (400 micrograms) as a rescue medication was inhaled after 120 minutes on each of the 5 study days.


RESULTS
The order of mean (+/- SEM) maximum tremor acceleration was as follows: 12 micrograms formoterol solution (67.92 +/- 4.54 cm x sec-2) < 24 micrograms solution (73.46 +/- 4.51 cm x sec-2) < 12 micrograms suspension (80.87 +/- 5.08 cm x sec-2) < fenoterol (84.13 +/- 4.21 cm x sec-2) < 24 micrograms formoterol suspension 88.54 +/- 6.26 cm x sec-2). Maximum increase in specific airway conductance ranged from 0.48 +/ 0.03 to 0.55 +/- 0.04 sec-1 x kPa-1 for all drugs (p > 0.05). No change in cardiovascular parameters occurred (p > 0.05).


CONCLUSIONS
No difference in the bronchial response to either formulation of formoterol was found. Tremor response to suspension aerosol (24 micrograms > 12 micrograms) was higher than that to solution aerosol (24 micrograms > 12 micrograms), indicating possible differences in systemic absorption because of a different deposition pattern. Rescue medication demonstrated systemic effects on tremor that were additive to those of formoterol.
Bauer
K
K
Department of Pneumology, University of Vienna Medical School, Austria.
Sertl
K
K
Kaik
B
B
Kaik
G
G
D000328:Adult; D000336:Aerosols / Q000145:classification; D001249:Asthma / Q000188:drug therapy* / Q000503:physiopathology; D001993:Bronchodilator Agents / Q000627:therapeutic use; D002319:Cardiovascular System / Q000187:drug effects; D004311:Double-Blind Method; D016503:Drug Delivery Systems; D004983:Ethanolamines / Q000008:administration & dosage* / Q000009:adverse effects* / Q000627:therapeutic use; D005260:Female; D005280:Fenoterol / Q000627:therapeutic use; D000068759:Formoterol Fumarate; D006801:Humans; D008297:Male; D008875:Middle Aged; D012123:Pulmonary Ventilation / Q000187:drug effects; D012137:Respiratory System / Q000187:drug effects*; D012996:Solutions; D013535:Suspensions; D014202:Tremor / Q000139:chemically induced* / Q000503:physiopathology
D000336:Aerosols; D001993:Bronchodilator Agents; D004983:Ethanolamines; D012996:Solutions; D013535:Suspensions; D005280:Fenoterol; D000068759:Formoterol Fumarate