Treatment Alternatives for the Addicted Patient
Primary care physicians are increasingly the initial point of contact for patients seeking mental health and substance use treatment.1,2 Patients with substance use disorders are more likely to have chronic medical comorbidities, including pain-related disorders (e.g., arthritis, headaches, and lower back pain), and psychiatric conditions, resulting in increased health care utilization and cost.3 In a 2014 national sample of adults age 18 and older, about 2 in 5 adults meeting criteria for substance use disorder also met criteria for a mental illness.4
Yet most adults in need of treatment are not receiving it due to lack of access, lack of financial resources, inadequate insurance coverage, stigma, or low motivation.5 In 2014, among an estimated 22.5 million adults age 12 or older who needed substance use treatment, only 4.1 million (18%) received treatment. Of those who received substance use treatment in 2014, 2.6 million (63%) received treatment at a facility, while 780,000 (19%) received treatment at a private doctor’s office.
Anti-relapse medications and medication-assisted treatment (MAT) can be effective in improving treatment outcomes in patients with substance use disorders.6 However, both are underutilized and underprescribed by most physicians.7,8 Primary care physicians can play an important role for patients during transitions of care by prescribing anti-relapse medications and MAT while patients await intake into specialized treatment facilities. This article will only review Food and Drug Administration (FDA)-approved medications for alcohol and opioid use disorders. These medications should be used in combination with a psychosocial treatment intervention for substance use disorders.9,10
There are four FDA-approved medications for patients with alcohol use disorder: disulfiram (Antabuse), acamprosate (Campral), naltrexone (ReVia), and long-acting naltrexone (Vivitrol). Patients who are screened and found to have harmful patterns of drinking can be considered for treatment with these medications.6 Medication choice may depend on factors such as patient motivation, treatment goals, medical comorbidities, medication tolerability and side effect profile, and the patient’s reproductive status. It is important that both the patient and provider agree on the immediate goals of treatment and be willing to continually monitor and reassess these goals as treatment progresses.6,11,12 (See Table 1 for further details on prescribing, monitoring, and adverse events associated with these medications.6,8,11,12)
Disulfiram is an alcohol-sensitizing medication that works by blocking the enzyme aldehyde dehydrogenase, thereby disrupting alcohol metabolism. The inhibition of this enzyme leads to the buildup of acetaldehyde in the blood, which is responsible for the unpleasant effect experienced by patients when alcohol is consumed.6,11 This disulfiram-ethanol reaction (DER) can vary in intensity based on the dose of disulfiram taken and the amount of alcohol ingested.6,11,12 The effects of disulfiram may last up to 2 weeks, as the body makes new aldehyde dehydrogenase enzymes to replace those irreversibly bound to disulfiram.6,12
Due to its adverse effects, disulfiram may be a strong deterrent to alcohol use for patients who are highly motivated about abstinence and who have the capacity to understand the consequences of drinking while on this medication. Family members of patients must also be informed of the possibility of a DER. It may be appropriate for those requiring supervised dosing to ensure medication adherence (i.e., ingestion of the medication under the supervision of an individual chosen by the patient) or those needing short–term therapy as a bridge or incentive to maintain abstinence.6,9,11,12 Patients should further be cautioned to avoid food and other drug preparations that may contain alcohol, which may potentially cause a DER.12 Patients also should have their liver function levels monitored regularly, and if there is a problem, be advised to stop the medication.
Acamprosate is an amino acid derivative that affects neurotransmission of gamma-aminobutyric acid (GABA) and glutamate. It has been shown to be helpful in relapse prevention and decreased alcohol consumption among those who do relapse.6,8,12 It may also be helpful for symptoms of protracted alcohol withdrawal.6,9,12 Acamprosate may be considered in patients with a primary goal of total abstinence, patients with liver disease or other medical co-morbidities, or patients on chronic opioids.6,11
Naltrexone is an opioid antagonist shown to be effective in cutting alcohol cravings and preventing relapse to heavy drinking by reducing the “reward” produced by drinking alcohol.8,12 It may be more effective in patients with significant cravings, co-occurring opioid use disorder, or a family history of alcohol use disorder.11
Naltrexone can be considered for patients who are ambivalent about abstinence, but who would like to reduce their alcohol consumption. It can be taken as a maintenance medication or as “targeted treatment” taken only when the patient is experiencing cravings.12 Patients must be abstinent from opioids for a period of 7 to 10 days prior to initiating it.6,12,13 Naltrexone has not been shown to cause significant elevations in liver enzymes and may result in improvement of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels with treatment.14
Extended-Release Naltrexone (Vivitrol)
Vivitrol is the extended-release, injectable formulation of naltrexone. Once injected, the medication remains in the body for up to 30 days. Due to the long-acting opioid blocking effects, patients should be counseled on alternative pain management strategies, such as nonopioid analgesia, regional anesthesia, conscious sedation, and general anesthesia. In emergent situations, the effects of Vivitrol can be overcome by administering higher amounts of short-acting opioids, with close clinical monitoring for respiratory depression.6 Vivitrol appears to be more effective when combined with other psychosocial interventions (e.g., therapy, 12-step programs) compared to treatment alone.6,11,12
Vivitrol can be considered for patients who tolerate oral naltrexone but have difficulty with medication adherence.6,11,12 As with oral naltrexone, patients need to be abstinent from opioids prior to administration and should carry a medical card indicating that they are taking naltrexone.6 As use of Vivitrol can lower tolerance for opioid medications, patients may be more susceptible to overdose and respiratory suppression with resumption of opioid use or any attempts to override the effect of Vivitrol by taking larger amounts of opioids.6,11,12