Chronic bromvalerylurea intoxication: dystonic posture and cerebellar ataxia due to nonsteroidal anti-inflammatory drug abuse.

Nalon-Ace and other nonsteroidal anti-inflammatory drugs (NSAID) containing bromvalerylurea (BVU) are sold as over-the-counter (OTC) drugs and are obtainable without prescription in Japan. A 32-year-old woman was diagnosed as having chronic BVU intoxication due to habitual use of Nalon-Ace. In addition to cerebellar ataxia and pyramidal signs well known in this condition, she showed an as yet non-described dystonic posture of the neck. Laboratory tests revealed an elevated concentration of serum organic bromide, iron deficiency anemia, and hyperchloremia. Brain magnetic resonance imaging (MRI) revealed definite cerebellar atrophy. We should consider the possibility of chronic BVU intoxication in peculiar neurological cases like ours.