[Theophylline poisoning--clinical course and treatment]

After about half a century of treatment of asthma and chronic obstructive pulmonary disease, theophylline still occupies a central position in the treatment of these conditions. Severe poisonings are rare and may occur as a result of chronic over-medication or acute self-poisoning. The clinical course depends not only on the amount taken and the peak serum concentration, but also on whether the intoxication is acute or chronic. The therapeutic range is narrow (55-110 mumol/l). Total body clearance of theophylline varies considerably between individuals, and drug interactions are common. These circumstances lead to relatively high risk of poisoning. Clinical features vary from moderate gastrointestinal discomfort, particularly nausea, tremor and tachycardia, to life-threatening conditions affecting the cardiovascular and central nervous systems. Treatment is discussed in connection with a presentation of three case histories.