REVISED FOOD AND DRUG ADMINISTRATION (FDA) LABELING GUIDELINES FOR THEOPHYLLINE ORAL DOSAGE FORMS

Abstract

The revised labeling for oral theophylline products recently issued in January 1995 by the United States' Food and Drug Administration is reviewed. Important revisions have been made in the following sections: Clinical Pharmacology, Indications and Usage, Warnings, Precautions, Overdosage, and Dosage and Administration. Specifically, factors known to alter theophylline absorption, disposition, and metabolism are now listed in the Clinical Pharmacology section, as are mean values for clearance and half-life of the drug in different populations (age groups, physiologic states). Theophylline is no longer indicated for the treatment of acute bronchoconstriction (consistent with present treatment guidelines), but only as maintenance therapy for chronic asthma symptoms. In the Warnings and Precautions sections, drugs and other factors that necessitate a change in theophylline dose are listed and details for properly monitoring serum theophylline concentrations have been added. The revised overdosage section now notes the frequency of clinical manifestations of overdosage, differences between acute and chronic overdose, and contains new recommendations for overdose management. Finally, in the Dosage and Administration section a slow (9-day) dosage titration scheme, aimed at reducing transient caffeine-like adverse effects, and a lower target peak serum concentration of 10 to 15 µg/mL are recommended.