A 44-year-old obese female patient ingested 200 mg diazepam and 1000 mg atenolol with suicidal intent. On admission to the clinic 24 hours later she was in deep coma, with a body temperature of 28.9 degrees C. The blood level of atenolol was 250 mg/l (therapeutic range 0.2-0.5 mg/l); this is the highest level yet recorded. She was treated with gastric lavage, instillation of charcoal and with orciprenaline, dopamine and dobutamine. She survived the poisoning without any untoward sequelae.