Caffeine alone may be an effective bronchodilator when used on a short-term basis;
however, a relatively large regular dosing of caffeine (eg, one to three cups of strong
coffee every six hours or less) would be required for significant, sustained bronchodilation,
since caffeine is a relatively weak and short-acting bronchodilator.
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Caffeine is a drug that is very similar to theophylline. Theophylline is a bronchodilator drug
that is taken to open up the airways in the lungs and therefore relieve the symptoms of asthma,
such as wheezing, coughing and breathlessness.
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Caffeine also helps lower respiratory muscle fatigue and can temporarily improve lung function
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up to two to four hours
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Cochrane's systemic review from 2010, 7 randomized trials of 75 people with mild to moderate asthma ...
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5 mg/kg body weight of caffeine achieved a peak bronchodilator effect within 2 h and lasted for six hours.
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