Xanthines in respiratory diseases.

Xanthines have been widely used for almost 50 years to treat bronchospastic conditions. They have a number of pharmacological properties, but the clinical applications are limited as bronchodilators. Current applications include intravenous preparations for acute asthma and prophylactically for other respiratory conditions that have bronchospasm as a common denominator. Sustained release preparations provide longterm, smooth plasma concentration levels. With easily performed and reliable blood levels, the risk of toxic, occasionally fatal side effects can be minimized. Not following patients with serial blood determinations of theophylline is almost inexcusable. A better knowledge of pharmacokinetics has established comprehensive guidelines, in particular, to its use in different clinical situations like pulmonary edema or liver failure, as well as its interaction with other drugs.