Background: Acute and chronic exposure to theophylline can cause serious signs and symptoms of poisoning. Additionally, with a narrow therapeutic range, toxicity could be observed even with therapeutic doses of theophylline. Epidemiological data on theophylline exposures in our country are extremely limited. The results of our study may improve the clinical management of theophylline poisoning in our country and elsewhere.
Aims: To present aetiological and demographic features, clinical findings and treatment attempts with regard to theophylline exposures reported to Dokuz Eylül University Drug and Poison Information Center (DPIC), between 1993 and 2011.
Study design: Descriptive study.
Methods: The data regarding demographics, date, time, type of exposure, route of and reason for exposure, signs and symptoms upon admission, clinical management and outcome were retrospectively evaluated.
Results: The DPIC recorded 88,562 poisoning calls between 1993 and 2011; 354 (0.4%) of them were due to theophylline exposure. The mean age of all cases was 24.1±15.4 (range between 1 month and 90 years). Females dominated all age groups (72.6%, 257 females). Intentional exposure was significantly higher in women than in men (88.2% vs. 68.2% for all age groups; p<0.001 for children; p<0.001 for adults; p<0.001 for all age groups). While 60.5% of the cases had no symptoms, severe signs of toxicity were present in 1.9% of theophylline exposure cases during the telephone inquiry. Signs and symptoms were found to be significantly more prevalent in adults than in children (p<0.01). The serum theophylline level was regarded as toxic in 74% (65 toxic levels) of theophylline measured cases. Clinical signs and symptoms were found to be significantly prevalent in cases with toxic theophylline levels (p<0.001). The rate of gastrointestinal decontamination procedures was higher than that of recommended gastrointestinal decontamination procedures by DPIC (83% and 66%, respectively). There were two fatalities (4.6%) associated with chronic theophylline toxicity and theophylline overdose in an acute setting for suicide (a 90 year-old and 25 year-old, respectively).
Conclusion: Although most of the theophylline exposure cases had no symptoms, some reported serious signs and symptoms of poisoning such as hypokalaemia, tachycardia and hyperglycaemia. DPICs have an important role in the management of theophylline exposure without unnecessary gastrointestinal decontamination procedures.
Keywords: Drug and Poison Information Center; Exposure; poisoning; retrospective; theophylline.