To identify risk factors for the development of seizures and cardiac arrhythmias after chronic, unintentional theophylline intoxication we monitored the clinical course of 72 consecutive patients referred to a regional poison center with chronic theophylline intoxication (serum theophylline concentration, ≥167 μmoI/L after protracted use). The median age of the sample was 47.5 years (range, 4 days to 91 years). Median peak theophylline concentration was 239 μmoI/L with a range of 167 to 722 μmoI/L A life-threatening event (LTE) occurred in 28 patients (39%) that included seizures in eight and a major cardiac arrhythmia in 22. The median peak (theophylline) of patients who had an LTE vs those who did not was 235.8 vs 238.7 μmoI/L. However, the median age of patients with an LTE compared with those without an LTE was significantly greater (70.5 vs 18.0 years). Stratification of data by chronologic age revealed a stepwise increase in the frequency of LTE with advancing years: patients more than 75 years old had a 16.7-fold greater risk of LTE than patients less than 25 years old (95% confidence interval, 3.56, 77.5) despite comparable intergroup median serum (theophylline). These data suggest the primary determinant of LTEs after chronic theophylline intoxication is chronologic age. Elderly patients have an inordinately greater risk of LTE than younger patients. Peak serum theophylline concentration cannot predict which patients with chronic theophylline intoxication will have an LTE. Finally, these data indicate that theophylline should be used cautiously and with frequent monitoring of serum theophylline concentrations in elderly patients.
(Arch Intern Med. 1990;150:2045-2048)
Register and get free email Table of Contents alerts, saved searches, PowerPoint downloads, CME quizzes, and more
Subscribe for full-text access to content from 1998 forward and a host of useful features
Activate your current subscription (AMA members and current subscribers)
Purchase Online Access to this article for 24 hours
Thank you for submitting a comment on this article. It will be reviewed by JAMA Internal Medicine editors. You will be notified when your comment has been published. Comments should not exceed 500 words of text and 10 references.
Do not submit personal medical questions or information that could identify a specific patient, questions about a particular case, or general inquiries to an author. Only content that has not been published, posted, or submitted elsewhere should be submitted. By submitting this Comment, you and any coauthors transfer copyright to the journal if your Comment is posted.
* = Required Field
Disclosure of Any Conflicts of Interest*
Indicate all relevant conflicts of interest of each author below, including all relevant financial interests, activities, and relationships within the past 3 years including, but not limited to, employment, affiliation, grants or funding, consultancies, honoraria or payment, speakers’ bureaus, stock ownership or options, expert testimony, royalties, donation of medical equipment, or patents planned, pending, or issued. If all authors have none, check "No potential conflicts or relevant financial interests" in the box below. Please also indicate any funding received in support of this work. The information will be posted with your response.
Some tools below are only available to our subscribers or users with an online account.
Download citation file:
Web of Science® Times Cited: 36
Customize your page view by dragging & repositioning the boxes below.
More Listings atJAMACareerCenter.com >
and access these and other features:
Enter your username and email address. We'll send you a link to reset your password.
Enter your username and email address. We'll send instructions on how to reset your password to the email address we have on record.
Athens and Shibboleth are access management services that provide single sign-on to protected resources. They replace the multiple user names and passwords necessary to access subscription-based content with a single user name and password that can be entered once per session. It operates independently of a user's location or IP address. If your institution uses Athens or Shibboleth authentication, please contact your site administrator to receive your user name and password.