Response: Anticipating New Medications

Abstract

Lawrence DeMarzo: My agency, House of the Crossroads, like other drug-free community-based agencies, has historically chosen not to use medications in its treatment regimens. That is changing now, through our involvement in NIDA’s Clinical Trials Network and our acquaintance with literature like Dr. Kampman’s article (Kampman, 2008). Much has changed since we started Crossroads. We know a lot more about addiction and treatment than we did 40 years ago. Although the agency is not using any medications yet, we are considering implementing a methadone-to-abstinence model for heroin abusers. Methadone appeals to us, because we have seen that it works, and because it seems to be a service line that produces stable utilization and retention, which a fee-for-service structure needs to generate revenue to cover the cost of care. I was impressed and encouraged by Dr. Kampman’s positive outlook on the potential for medications to treat stimulant abuse. The drugs in this class, particularly crack cocaine and methamphetamine, have had the most devastating effects on our community and present the greatest challenge to us in terms of providing effective treatment. Michael Bogenschutz: At our large, outpatient substance abuse program at the University of New Mexico, we generally try to treat drug abusers pharmacologically to help them through detoxification. We used amantadine for a number of years and have also used a number of other medications—including baclofen, disulfiram, and propranolol— based on what has seemed most promising at the time. With each of these medications, some patients will say that it made a big difference. I believe they help, but I wonder how much. The empirical findings for all of them are still equivocal—some promising results on the one hand, but without substantiation in large clinical trials. On the other hand, I am sure that the structure and support we supply along with medications contribute significantly to our patients’ recoveries. John Roll: Do you think those medications you use affect addiction directly or do they affect co-occurring psychiatric conditions that may be enabling or facilitating the drug use? Bogenschutz: I think they affect addition directly. These patients are in our primary addiction treatment program, and they may or may not have co-occurring disorders. We target early withdrawal symptoms, like craving, and hope to normalize the function of a person’s brain. Disulfiram or gamma-aminobutyric acid (GABA)-ergic medications can also affect the reinforcement value or effects of cocaine or methamphetamine. Roll: One point that I think bears highlighting is that medications compensate for some of the reinforcing effects of drugs, but only some. At one level, drugs reinforce abuse because of their pharmacology, and it makes perfect sense to target those aspects of reinforcement with pharmaceutical interventions. However, drugs also accrue reinforcing efficacy by other means, like the associations of a drug-using peer group. I’ve heard anecdotal evidence that some women initiate use of methamphetamine to take advantage of its anorectic properties and control weight. Sex workers have told me that they could never do their job without drugs, so they have an economic incentive to continue using them. Medications don’t directly modify these sorts of reinforcement and therefore may not constitute treatment all by themselves. Bogenschutz: A good example of that point is the experience with naltrexone. When naltrexone was first released, many thought it would be 100 percent effective for opiate dependence, because it functions like an antidote for heroin. However, in the real world, naltrexone has had only a small impact on opioid dependence treatment. Most patients simply won’t take it; it causes dysphoria in opiate abusers, and it doesn’t decrease craving. Patients who do take it can simply stop if they want to resume heroin use. We would likely face similar problems with some of the medications Dr. Kampman discusses, particularly the cocaine vaccine. DeMarzo: I have heard Nora Volkow, NIDA’s director, make the case that developing effective medications to treat stimulant addiction is an avenue to reducing the stigma of addiction and legitimizing addiction treatment services. That makes sense to me, and it’s one of the reasons I find this research exciting.