Intoxication with over-the-counter antitussive medication containing dihydrocodeine and chlorpheniramine causes generalized convulsion and mixed acidosis

Abstract

We report a 35-year-old man who was referred to our hospital with generalized convulsion and mixed acidosis presumably caused by abuse of SS-BRON™ tablets, an over-the-counter (OTC) antitussive medication sold in Japan. These tablets contain dihydrocodeine phosphate, methylephedrine, chlorpheniramine, and caffeine. Although it is difficult to discern which component caused these symptoms, it seems that dihydrocodeine phosphate or methylephedrine was involved in the addiction to SS-BRON™ and chlorpheniramine may have caused the generalized convulsion. It should be recognized that an OTC antitussive, which is quite easy to obtain, can be abused and subsequently induce serious intoxication. © 2008 The Japanese Society of Internal Medicine.