MARIO ANZUONI / REUTERS Cory Monteith in Los Angeles, Sep. 7, 2010.

The Vancouver coroner’s office revealed that “Glee” star Cory Monteith died of a toxic mixture of alcohol and heroin, weeks after leaving rehab for substance misuse. His death highlights the dangers of the post-rehab period, and why patients are most vulnerable just after they receive treatment.

Monteith’s history of distress began early: in an interview with Parade, the 31-year old admitted that at 13, he drank and smoked marijuana and by 16, he had attended 12 different schools, including some described in the article as “alternative programs for troubled teens.”

And that’s where the “system” —the programs and facilities and treatment strategies most commonly called into action to help addicts — started to fail Monteith. The evidence suggests that many of these institutions are ineffective or even potentially harmful— “troubled teen” is not a standardized diagnosis and most of these largely unregulated residential centers do not effectively identify or treat the most common psychiatric issues that affect teens with behavior problems, including addictions. The programs certainly didn’t help Monteith, who dropped out and, by his own admission, only continued his drug use.

At 19, his mother and friends staged an intervention. Traditional interventions, which force the addict to either get help or face consequences such as prison, are half as effective as approaches that use more supportive methods of motivation, such as Community Reinforcement and Family Therapy (CRAFT), which focuses on building a social environment that reinforces sobriety and discourages drug use. While tough interventions are often used as a last resort, most families are not even aware of the less forceful approaches. And unfortunately, relapse is more common after such compulsory treatment.

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Monteith relapsed almost immediately, admitting in Parade that “I did the stint but then went back to doing exactly what I left off doing.” Part of the problem may have been with the rehab program itself; research suggests that many programs don’t take advantage of available medications approved by the Food and Drug Administration (FDA), don’t provide talk therapy program that have been proven effective, and instead rely on punishing, boot-camp style intimidation tactics such as humiliating emotional attacks and re-enactments of trauma that are known to send teens back to drugs or make them even more rebellious.

Acting gave Monteith a purpose and goals— at least for a while, and helped to tame his addictions. But despite his enormous success as Finn Hudson on “Glee,” Monteith was lured back to drugs in the months before his death.

He did a second round of rehab, checking himself into a facility last April. While it’s not clear why he was receiving treatment, if, given the coroner’s report, he was seeking help for heroin addiction, a lack of tolerance may have contributed to his death. Heroin, an opioid, produces tolerance, so that users not only need more drug to experience a “high,” but also higher amounts to overdose. Abstaining for a few weeks, as many rehab programs require, lowers this tolerance so if an addict were to use again, a previously normal dose could become fatal. Most deadly overdoses occur either in new users or in experienced addicts following a period of abstinence, such as in prison or rehab. Indeed, the first two weeks after prison carry an overdose risk rate that is more than 120 times higher than typical among users, according to one study.

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Which is why leading experts like the National Institute on Drug Abuse have long advocated for maintenance treatment with drugs like methadone or Suboxone to treat opioid addictions, rather than abstinence. Research shows that these treatments can lower overdose and disease-related death rates but they remain controversial, since most residential rehab facilities prefer the strategy of total abstinence from any medications, even therapeutic ones for addiction.

Only last year did Hazelden, which pioneered this abstinence approach with the “Minnesota Model,” on which 90% of American treatment is based, begin adding maintenance therapies. As I wrote then, Hazelden did so because too many people were dying in the first few months after leaving rehab, like Monteith. Abstinence was proving to be doubly harmful— addicts were turning back to their drugs of choice, and when they were, their lower tolerance was putting them in danger of overdosing. “[Those] deaths were certainly a major issue in our decision making,” Hazelden’s chief medical officer, Dr. Marvin Seppala, said.

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Adding to the danger is the fact that, as in Monteith’s case, most overdoses do not involve just one class of drugs. Monteith combined alcohol with heroin — two drugs that depress breathing, which can be a recipe for death. About 60% of so-called opioid overdoses — overdoses blamed on painkillers or heroin— are actually the result of such combinations. While some addicts will intentionally take such mixtures to intensify the high, many are unaware of issues like tolerance or the dangers of combining drugs.

And there may be one last way in which Monteith’s death can serve as a lesson for how to serve addicts better. There is a safe and nontoxic antidote, naloxone, to treat opioid overdose, which I have argued should be available in first aid kits so more potential victims might be saved. Improving such rescue therapies, as well as those used in rehab treatment programs, could lead to fewer tragedies like Monteith’s death.