Hypokalemia, hyperglycemia and plasma catecholamine activity after severe theophylline intoxication

To determine if differences in the rate of hypokalemia and hyperglycemia between victims of acute versus chronic theophylline intoxication relate to alterations in plasma catecholamine activity, we evaluated plasma catechols in three groups of patients: victims of acute theophylline intoxication (n = 10), chronic theophylline overmedication (n = 3), and healthy controls (n = 6). There were no differences in peak serum theophylline concentration between acute and chronic groups (86.6 vs 73.0 mcg/mL, p = NS). Among those with acute intoxication mean (+/- SEM) serum potassium was 2.80 +/- .16 mEq/L while mean serum glucose was 208 +/- 26 mg/dL. In contrast, those with chronic intoxication had a mean serum potassium of 4.10 +/- .70 mEq/L with a mean serum glucose of 139 mg/dL (p < .0001 and p < .04 for between-group potassium and glucose, respectively). Potassium and glucose concentrations of those with chronic theophylline intoxication were similar to those of controls. Plasma epinephrine was higher in those with acute theophylline intoxication than in victims of chronic overmedication and controls (282 vs 133 vs 58 pg/mL, p < .003). Plasma norepinephrine and dopamine in contrast were significantly higher in those with chronic overmedication than in those with acute intoxication and controls (norepinephrine 1395 vs 965 vs 268 pg/mL, p < .008; dopamine 198 vs 148 vs 39 pg/mL, p < .009). These data suggest that the pattern of glucose and potassium disturbances after acute theophylline intoxication parallel differences in plasma epinephrine concentrations. This supports theories that hypokalemia is the result of enhanced beta-2 receptor stimulation.