Theophylline overdose Adverse effects: incidence study

The case records of 42 patients with acute (n = 27) or chronic (n = 15) theophylline overdosing were retrospectively analysed. Hypotension, hypokalaemia and acidosis were seen in 44, 44 and 56% of the acute group, respectively, but were not seen in the chronic group. The differences in frequencies of these features were still apparent after correction for the significantly higher peak theophylline levels in the acute patients (mean of 97 mg/L compared with 39 mg/L in the chronic group). Seizures were reported with similar frequencies in both groups (27-30% of subjects) but within the acute group these were significantly more frequent in patients ,whose peak theophylline levels exceeded 100 mg/L (n = 8) than in the remaining 19 patients (88% vs 5%, respectively). Within the chronic group, seizures were significantly more frequent in patients with peak levels> 40 mg/L (n = 5) than in the 10 patients with levels < 40 mg/L (80% vs 30%, respectively). Major cardiac arrhythmias (frequent ventricular ectopy, atrial fibrillation and cardiac arrest) occurred in 27% of the chronic group (4 patients) and 19% of the acute group (5). Four patients died: 2 acute patients (peak theophylline levels> 100 mg/ L)and 2 chronic patients (levels < 60 mg/L, both with congestive heart failure). One acute patient (peak level 270 mg/L) suffered a residual short term memory deficit after having had status epilepticus and hypotension for 24 hours.

The authors concluded that '. _ . contrary to current guidelines, patients with acute single ingestion and theophylline levels below 100 mg/L may be managed with supportive care alone' Haemoperfusion should be considered in acute patients with theophylline levels above 100 mg/L and in chronically overdosed patients with levels over 60 mg/L (or over 40 mg/L if respiratory failure, congestive heart failure or liver disease are also present). Olson KR,Benowltz NL. Woo OF, Pond SM Ameflcan Journal of Emergency Medicme 3. 386-394, Sep 1985

0157-7271/86/1026-0009/0$01.00/0 © ADIS Press Reactions'" 25 Jan 1986 9