Nonprescription bronchodilator medication use in asthma.
OBJECTIVE
Many persons with asthma self-medicate with widely available and potentially hazardous nonprescription medicines. This study assessed the demographic and clinical covariates of self-treatment with over-the-counter asthma medications (OTCs).


METHODS
We conducted an analytical investigation using questionnaires and measures of lung function, comparing OTC and prescription medication users. We recruited adults with asthma by public advertisement.


METHODS
We studied 22 exclusive prescription asthma medication users, 15 exclusive OTC users, and 13 other subjects who combined prescription medication use with self-treatment with asthma OTCs. All but one OTC user self-medicated with a nonselective, sympathomimetic metered-dose inhaler.


RESULTS
Taking income, access to care, and self-assessed disease severity into account, male gender was strongly associated with exclusive OTC use alone (odds ratio [OR]=8.9, 95% confidence interval [CI]= 1.3 to 61) and mixed OTC-prescription medication use (OR=9.7, 95% CI=1.1 to 83). The covariates of income, access to care, and self-assessed disease severity provided significant additional explanatory power to the model of exclusive OTC use (model chi2 difference 11.3, 5 df, p<0.05). Pulmonary function was similar among OTC and prescription medication users. However, prescription medication users' self-assessed asthma severity (mild compared to more severe) was associated with postbronchodilator reversibility of FEV1 obstruction (6% vs 18% reversibility, p<0.05) while exclusive OTC users' self-assessed severity showed the reverse pattern (19% vs 8%, p=0.2).


CONCLUSIONS
Asthma education programs attempting to discourage unregulated bronchodilator use should give consideration to this profile of the "asthmatic-at-risk."
Kuschner
W G
WG
Department of Medicine, and the Cardiovascular Research Institute, University of California, San Francisco, USA.
Hankinson
T C
TC
Wong
H H
HH
Blanc
P D
PD
D000328:Adult; D000402:Airway Obstruction / Q000188:drug therapy / Q000503:physiopathology; D001249:Asthma / Q000188:drug therapy* / Q000503:physiopathology; D001294:Attitude to Health; D001993:Bronchodilator Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D016009:Chi-Square Distribution; D016001:Confidence Intervals; D011307:Drug Prescriptions; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects; D006297:Health Services Accessibility; D006801:Humans; D007182:Income; D008168:Lung / Q000187:drug effects / Q000503:physiopathology; D008297:Male; D009330:Nebulizers and Vaporizers; D004366:Nonprescription Drugs / Q000008:administration & dosage / Q000627:therapeutic use*; D016017:Odds Ratio; D010353:Patient Education as Topic; D010366:Peak Expiratory Flow Rate / Q000187:drug effects; D012307:Risk Factors; D012651:Self Medication; D012647:Self-Assessment; D012737:Sex Factors; D011795:Surveys and Questionnaires; D013566:Sympathomimetics / Q000008:administration & dosage / Q000627:therapeutic use; D014797:Vital Capacity / Q000187:drug effects
D001993:Bronchodilator Agents; D004366:Nonprescription Drugs; D013566:Sympathomimetics