Another recent trial randomized adolescents dependent on cannabis to placebo or N-acetylcysteine 1200 mg twice a day. Those on the active drug were 2.4 times more likely than those on placebo to have negative urine tests with a number needed to treat of 7.48 Both trials ran for about 3 months. Neither drug is FDA approved to treat marijuana dependence.
For opioid dependence. As maintenance medication for patients dependent on opioids, both methadone and buprenorphine have been shown to reduce the use of illicit opioids, lower mortality, and improve retention compared with treatment without medication.49 Methadone would be a better choice than buprenorphine, which is a partial agonist with a ceiling on both its good (eg, stopping craving) and bad (eg, overdose risk) effects. In an open-label observational study of patients’ preferences, those who chose methadone maintenance over buprenorphine were twice as likely to remain in treatment.50 Both drugs are FDA-approved for treating opioid dependence.
Methadone is a full agonist that can be given for opioid dependence only in a federally licensed methadone maintenance clinic. It has been shown to reduce the use of other opioids, reduce criminal behaviors,51 improve function in many areas,52 and reduce mortality.53 In a cohort study of Massachusetts Medicaid data, methadone reduced mortality, which was 75% higher among those receiving abstinence-based treatment.52,54
Buprenorphine (alone and in combination with naloxone), effectively reduces the use of illicit opioids and improves functional status.55-57
Naltrexone, an opioid antagonist, may be effective in the treatment of opioid dependence. As with disulfiram for alcohol dependence, a major limitation of naltrexone for opioid dependence is noncompliance. But once a patient has been on oral naltrexone, he or she can be switched to naltrexone IM, which can be administered every 4 weeks. A Cochrane review published in 2011 found no evidence that naltrexone was superior to placebo, 58 but since then another randomized clinical trial has been published that found naltrexone 380 mg IM every 4 weeks was superior to IM placebo. Patients on naltrexone were more likely to remain in treatment and have opioid-free urine tests, and reported less craving for opioids.59 Both oral and depot injection naltrexone are FDA approved for treatment of opioid dependence. No comparisons of naltrexone vs either methadone or buprenorphine have been published.
To learn more about pharmacotherapy for opioid dependence, see “Diagnosing and treating opioid dependence” (J Fam Pract. 2012;61:588-596).
DEALING WITH THE CHALLENGES
As noted earlier, some patients with substance use disorders, like some patients with depression or hypertension, respond well to care and counseling, and some do not. Just as with other conditions, consultation with a specialist often helps.
A major difference in arranging consultations for patients with substance use disorders, however, is that clinicians who specialize in substance abuse and dependence often work in health care systems that are largely, or entirely, separate from those in which primary care physicians typically work. This, plus the stigma that surrounds problems with substance use, presents barriers to patients, who may shy away from going across town or to another city to see a provider they don’t know for a problem they’re either resistant to “owning” or ashamed of.
Yet it is possible to reach across this divide and make it easier for patients. One way to do that might be to partner with a local alcohol- and drug-treatment program so that your patients are referred, not to a faceless agency, but rather to a specific clinician; you might even call the provider while the patient is in your office so they can “meet.” Another approach, taken by some multispecialty practices, is to add psychotherapists to the staff so that patients can simply walk down the hall to obtain the mental health care they need.
Reaching across this divide is also a useful strategy for primary care physicians, who may welcome opportunities to meet with someone from a local treatment agency, not just for referrals but to learn more about treating patients with substance use problems. The Patient Protection and Affordable Care Act, which cites substance use disorders as one of 6 chronic health conditions that primary care medical homes are expected to address, may lead to better integration of health care systems that address physical health, as well as mental health and substance use disorders.