MICHAEL E. CHARNESS, M.D., CHIEF OF STAFF, VA BOSTON HEALTHCARE SYSTEM
V E TE R AN S AFFAI R S & M I LITARY M E D I CI N E O UTLO O K
Next to alcohol, cocaine accounts for the second-most common substance use disorder in the VA system, and there is currently no FDA-approved pharmacological treatment for cocaine use. This is a dangerous circumstance for veterans: According to Christopher Stauffer, M.D., a psychiatrist at the San Francisco VAMC and professor of psychiatry at the University of California-San Francisco, between 30 to 60 percent of patients receiving methadone maintenance treatment (MMT) for opioid use disorder are also actively using cocaine – and dropout rates from MMT and other opioid use treatment programs are as high as 80 percent for cocaine users. The mortality rate of concurrent users of cocaine and heroin is 14 times higher than the general population’s. Two years ago, Stauffer began recruiting for a trial aimed at reducing active cocaine use among veterans receiving MMT therapy. Cocaine use is known to be driven by social stress
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A model showing the location (dotted circle) where alcohol interacts with the L1 molecule to reduce its “stickiness.” and associated with hyperreactivity of the brain’s stress response system – the hypothalamic-pituitary-adrenal (HPA) axis. Stauffer hypothesized that administering the hormone oxytocin to cocaine users might help to weaken this hyperreactivity (oxytocin, which plays a role in parent-child and social bonding, is produced in the hypothalamus and released by the pituitary gland), improve engagement in psychosocial treatments, and perhaps reduce subjects’ desire for cocaine. “There is a lot of animal data showing that oxytocin is helpful for almost every substance of abuse, [including] alcohol, opioids, cocaine, methamphetamine,” Stauffer said. “We don’t really know why yet. Substance abuse highjacks the same neuro-circuitry that is used for social relationships, the same reward. And we know that when people develop
a substance abuse disorder, their relationships with other people kind of fall to the wayside.” It’s also known, Stauffer said, that the brains of cocaine users down-regulate the production of oxytocin. “So, the thought is that if maybe we give them oxytocin from the outside, that might help rebalance things.” This isn’t Stauffer’s only study involving oxytocin and substance use, and he hasn’t yet found that oxytocin, by itself, has reduced subjects’ substance use – though he has noticed, anecdotally, that patients receiving oxytocin seem more engaged in the clinic’s activities: They attend more often and seem more engaged. “I’m starting to believe that you need to give patients something to shift their attention toward,” Stauffer said. “Just giving them the oxytocin without giving them the support I don’t think is going to be as helpful. I think you need the oxytocin plus a positive social relationship to kind of transfer their reward system onto.”
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