Therapeutic drug monitoring in the opioid substitution treatment

Opioid substitution treatment (OST) is an evidence-based intervention and different substances are available nowadays as a treatment option. Methadone, a long-acting synthetic opioid, is available e.g. for more than 40 years and was the first widely used opioid for the treatment of heroin dependence, e.g. in Switzerland since 1975. The Swiss Federal Office of Public Health does not provide any information on the therapeutic reference range in its summary of medical recommendations "Substitution-assisted treatment of opioid dependence". The German S3 guidelines "Medication-related disorders" mentions Therapeutic Drug Monitoring (TDM) and refers to the current "Consensus Guidelines for Therapeutic Drug Monitoring in Neuropsychopharmacology: Update 2017" in which the recommendation levels for the use of TDM are listed. The level of recommendation in the OST differs from substance to substance and is e.g. for methadone (level 2: recommended) the same as for the atypical antipsychotics aripiprazole or risperidone. In fact, TDM for OST still is insufficiently integrated into clinical routine. The new S3 guideline "Opioid-related Disorders" is expected this year and is registered by the Association of the Scientific Medical Societies in Germany (AWMF).