How important are saunas in a drug rehab?

Most drugs of abuse are metabolized by the liver and excreted by the kidneys in urine or by the liver in bile.  There is no evidence that perspiration, which is presumably the mechanism by which a sauna would work, contributes significantly to this process or achieves results that would not otherwise be achieved through normal processes.  With saunas there is also the risk of medical complications through electrolyte loss and imbalance, dehydration and hyperthermia.  Given the lack of scientific evidence to support detoxification through this method, I would not recommend it as a first choice for treatment.