Are empty methadone bottles empty? An analytic study.

Background: Methadone maintenance treatment is the most widely prescribed treatment for opiate dependence with proven benefits for patients. In naïve users or in case of recreational misuse, methadone can be a source of potentially lethal intoxications, resulting in fatal overdoses. A few cases of infantile intoxications have been described in the literature, some of which resulted in death. Nowadays, more than 50,000 bottles are used every day in France, most of which are thrown away in the bin. Relatives at home, especially children, can have access to these empty bottles. This study aims to determine whether the residual quantity of methadone in the bottles is associated with a risk of intoxication for someone who has a low tolerance to opiates, such as a child.

Methods: The methadone dosage left in a sample of 175 bottles recapped after use by the patients taking their maintenance treatment in an addiction treatment program centre was analysed during a 2-week period in March 2013.

Results: The mean residual quantity of methadone left in each bottle after use is 1.9 ± 1.8 mg and 3.3 ± 2.4 mg in the sample of 60 mg bottles.

Conclusions: There is a potential danger of accidental overdose with empty bottles of methadone syrup, especially for children. To take into account this hazard, several harm reduction strategies can be proposed, such as favouring the taking of the treatment within the delivery centres rather than the 'take home' doses, asking methadone users to bring back their used bottles, and raising patients' awareness of the intoxication risks and the necessary everyday precautions. For stable patients with take home methadone, the use of capsules could be considered.