A study of self poisoning with oral salbutamol--laboratory and clinical features

1. The recent increase in asthma mortality coupled with reports of fatal asthma associated with beta-2-agonist therapy, has stimulated interest in the plasma concentrations of beta-2-agonists that produce systemic toxicity. 2. We prospectively studied 17 patients (9 male), mean age 23 years (range 2-72), who attended the emergency departments of hospitals throughout the United Kingdom having recently ingested an overdose of salbutamol. 3. Clinical, laboratory, ECG data, plasma and urine samples were obtained from each patient. Plasma was assayed for salbutamol concentration using a high performance TLC-photodensitometric method. 4. The mean (+/- s.d.) salbutamol dose reported to have been ingested was 89(+83)mg and the mean plasma salbutamol concentration was 166 (range 18-449) ng ml-1. The mean plasma potassium was 2.9 (s.d. +/- 0.6) mM (n = 16). None of the patients in this study developed serious cardiac dysrrhythmias. 5. There were significant correlations between the plasma salbutamol concentration and plasma potassium concentration (r = -0.85; P < 0.00005) and between plasma salbutamol concentration and pulse rate (r = 0.66; P < 0.005). 6. We conclude that in these patients, without respiratory decompensation, suprapharmacological plasma concentrations of salbutamol were tolerated without serious cardiac arrhythmias or any fatalities.