Klin Farmakol Farm. 2025;39(4):199-205 | DOI: 10.36290/far.2025.069

The importance of therapeutic monitoring of theophylline

Kristina Pechandová

Oddělení klinické farmacie, Nemocnice Strakonice, a. s.

Katedra sociální a klinické farmacie, Farmaceutická fakulta v Hradci Králové, Univerzita Karlova

Theophylline, a worldwide known and long-used bronchodilators in the treatment of lung diseases, has a narrow therapeutic range. The considerable interindividual variability in its pharmacokinetic parameters, the weak correlation between dose and plasma concentration, and the close relationship between plasma concentration and clinical effect make it a suitable candidate for therapeutic drug monitoring. Theophylline is mainly used in the treatment of pulmonary diseases, but its expected bronchodilator effect is only exerted when higher plasma levels are reached. During treatment, their regular determination is necessary to optimize therapy. High levels are associated with a significant risk of the development of serious and fatal adverse effects, which limit the clinical use of theophylline. When assessing plasma levels, it is necessary to take into account whether acute intoxication or long-term chronic overdose is involved, which is associated with a higher incidence of adverse effects already at lower, often still therapeutic, levels. For a correct interpretation, we must consider a number of variables determined by patient characteristics, the properties of the theophylline molecule and other concomitant medications It is therefore recommended to consult a clinical pharmacist or pharmacologist to determine the optimal dose for the patient, evaluate individual pharmacokinetic parameters, model the course of concentrations after initiation of treatment, and monitor subsequent plasma levels. If the risks outweigh the benefits, the drug should be discontinued in a timely manner.

Keywords: theophylline, therapeutic drug monitoring, intoxication, pharmacokinetics.

Received: September 10, 2025; Revised: December 2, 2025; Accepted: December 5, 2025; Published: December 22, 2025  Show citation