USA. Accidental overdose of concentrated oral morphine solutions has resulted in serious adverse events and deaths, according to a ‘Dear Healthcare Professional’ letter issued by Elan Pharmaceuticals in the United States. In most cases, oral morphine solutions that were ordered in mg were mistakenly interchanged for mL, resulting in a 20-fold overdose. Elan distributes three concentrated oral solutions containing morphine 20 mg/mL (Roxanol, Roxanol-T and Roxanol 100). In order to prevent medication errors, the company has requested that prescribers write prescriptions for oral morphine solutions clearly stating the required concentration of oral solution, the intended morphine dose in mg and the corresponding volume in mL.

Reference:
‘Dear Healthcare Professional’ letter from Elan Pharmaceuticals, October 2003. Available from URL: http://www.fda.gov