[Chronopharmacology of reversible airway obstruction]

Nocturnal coughing and/or asthmatic attacks may be observed in each asthmatic patient. These symptoms are so typical, that they may serve for early diagnosis of this disease. "Nocturnal asthma" is the consequence of an aggravation of the circadian variation in lung function that occurs also in healthy people. It goes back to a complex network of interacting neuro-humoral mechanisms with a high (bronchoconstricting) parasympathetic tone at night and a high (bronchodilating) sympathetic tone at daytime. There are many possible reasons for the pathological aggravation at night in an individual patient. The therapy of "nocturnal asthma" is based on a thorough inhibition of inflammation, being executed by the consequent therapy of the disease itself. Acute nocturnal attacks may be prevented best by oral theophylline in retarded drug formulations or by inhalation of long-acting beta-sympathomimetics just before going to bed.