Myoclonic jerks due to acute bromovalerylurea intoxication.

Background: Bromides are still sold as sedatives, antitussives, and anticonvulsants in many countries. Bromovalerylurea is a bromide-containing sedative-hypnotic that is occasionally combined with non-steroidal anti-inflammatory drugs in over-the-counter products. Chronic intake of excessive bromovalerylurea can produce bromide intoxication, but acute bromovalerylurea intoxication presenting with myoclonic jerks has never been described.

Case Report: A 23-year-old woman was brought to our emergency department with unusual drowsiness. Her physical examination was normal except for frequent myoclonic jerks in all extremities that could be triggered by moving the patient or by noxious stimuli. Initial blood tests results were normal; the serum bromide concentration was 81.0 mg/L (reference <10 mg/L). Treatment with intravenous normal saline and furosemide resulted in gradual improvement in her drowsiness and myoclonic jerks. By the second hospital day, she was normal. A brain magnetic resonance imaging (MRI) was normal. At a 2-month follow-up visit, the patient had no neurological sequelae.

Discussion: Chronic bromide intoxication caused by long-term abuse of bromovalerylurea may present as psychiatric or neurologic abnormalities. Our case of acute bromovalerylurea intoxication presented with severe myoclonic jerks and lethargy. The serum bromide concentration was similar to the reported concentrations in acute bromide intoxications. Treatment with normal saline and diuretics results in increased clearance of bromide and an improvement in clinical effects.

Conclusion: Myoclonic jerks may be one of the major presentations of acute bromovalerylurea intoxication. Physicians should consider bromide intoxication in the differential diagnosis of the causes of myoclonic jerks.