Medication-Assisted Treatment (MAT)

Medication-assisted treatment (MAT) is the use of FDA-approved medications, in combination with counseling and behavioral therapies, to provide a whole-patient approach to the treatment of substance use disorders. MAT is currently available for opioid use disorder (OUD) and alcohol use disorder (AUD), and represents the gold standard of evidence-based care for both conditions.

Despite a robust and growing evidence base, MAT remains underutilized and widely misunderstood — often dismissed with phrases like "trading one drug for another." This framing misrepresents both the pharmacology of MAT medications and the nature of addiction as a medical disease. This article explains what MAT is, what the evidence shows, which medications are available, and how to access them.

The Evidence Base for MAT

The case for MAT — particularly for opioid use disorder — is among the strongest in all of addiction medicine. Key findings include:

• A 2020 report from the National Academies of Sciences, Engineering, and Medicine concluded that medications for OUD reduce the risk of opioid overdose death, reduce illicit opioid use, increase treatment retention, and improve social functioning.
• Buprenorphine and methadone treatment are associated with a 50% or greater reduction in opioid overdose mortality, according to research published in Addiction.
• Naltrexone (extended-release injectable) for OUD shows comparable efficacy to buprenorphine in patients who are fully opioid-detoxified, with the added benefit of being non-opioid and having no abuse potential.
• For alcohol use disorder, naltrexone reduces both relapse to heavy drinking and the likelihood of drinking on any given day. Acamprosate reduces withdrawal-related discomfort and supports abstinence. Both have robust evidence from randomized controlled trials.

Medications for Opioid Use Disorder

Buprenorphine

Buprenorphine is a partial opioid agonist that binds to the same receptors as heroin, fentanyl, and prescription opioids but produces a ceiling effect — meaning it has limited ability to produce euphoria and overdose risk is substantially lower than full opioid agonists. It reduces cravings, prevents withdrawal symptoms, and blocks the effects of other opioids if used.

Buprenorphine is available in several formulations, including sublingual films and tablets (Suboxone, which combines buprenorphine with naloxone to deter misuse), and a long-acting injectable (Sublocade). As of 2023, the DEA waiver requirement (the "X-waiver") that previously limited which physicians could prescribe buprenorphine has been eliminated, expanding access significantly.

Buprenorphine can be prescribed in office-based settings, making it far more accessible than methadone. It is appropriate for most patients with opioid use disorder and is generally the first-line medication choice in outpatient settings.

Methadone

Methadone is a full opioid agonist that eliminates withdrawal and cravings by occupying opioid receptors. For opioid use disorder treatment, methadone must be dispensed through a federally certified Opioid Treatment Program (OTP), also called a methadone clinic. Patients typically visit the clinic daily for dispensing, at least initially.

Methadone has one of the longest evidence bases in addiction medicine — its efficacy for OUD has been documented in clinical research since the 1960s. It is particularly effective for patients with severe OUD who have not responded to buprenorphine, and for patients who prefer the structure of daily clinic attendance.

The primary limitations of methadone are the requirement for daily clinic attendance (a significant barrier for patients with work, childcare, or transportation challenges) and its potential for cardiac side effects at high doses, requiring medical monitoring.

Naltrexone (Extended-Release Injectable)

Naltrexone is an opioid antagonist — it blocks opioid receptors entirely, preventing opioids from producing any effect. The extended-release injectable formulation (Vivitrol) is administered once monthly by a healthcare provider, eliminating daily medication adherence challenges and medication misuse potential.

Naltrexone is not an opioid and has no abuse potential. However, it requires complete opioid detoxification before initiation — patients must be fully opioid-free for 7–10 days (depending on the specific opioid) before starting naltrexone. This requirement is a significant barrier, as it necessitates a period of withdrawal that many patients are unwilling or unable to complete.

Naltrexone is often preferred in settings where carrying a controlled substance is problematic (e.g., for certain occupations or in criminal justice contexts) and for patients with strong intrinsic motivation who have successfully completed detoxification.

Medications for Alcohol Use Disorder

Naltrexone (Oral and Injectable)

Naltrexone reduces the pleasurable effects of alcohol by blocking opioid receptors involved in alcohol's reward pathway. Clinical trials have demonstrated that naltrexone reduces heavy drinking days, reduces the probability of relapse to heavy drinking, and is well-tolerated by most patients. It can be prescribed in primary care settings.

Acamprosate

Acamprosate works differently from naltrexone — it helps normalize the brain chemistry dysregulated by chronic alcohol use, reducing post-acute withdrawal symptoms including anxiety, insomnia, and dysphoria that can persist for weeks or months after cessation and drive relapse. Acamprosate is most effective for patients who have already achieved abstinence and want to maintain it.

Disulfiram

Disulfiram (Antabuse) works by blocking the metabolism of alcohol, causing intensely unpleasant symptoms (flushing, nausea, vomiting, palpitations) if alcohol is consumed. It is primarily effective for highly motivated patients or when adherence can be monitored (e.g., by a family member or in a supervised setting). It is rarely used as a first-line medication due to adherence challenges and safety concerns.

MAT and Co-Occurring Mental Health Conditions

MAT does not preclude treatment for co-occurring mental health conditions — in fact, integrated treatment that addresses both simultaneously typically produces better outcomes. Clinicians must be thoughtful about drug interactions (particularly between MAT medications and psychiatric medications) and should evaluate for co-occurring conditions in all patients initiating MAT.

For patients with opioid use disorder and co-occurring depression, anxiety, or PTSD, the stabilization that MAT provides often makes engagement with behavioral health treatment more feasible. See our section on co-occurring disorders for more.

Accessing MAT

To find buprenorphine prescribers, the SAMHSA Buprenorphine Practitioner Locator (samhsa.gov) lists certified prescribers by location. To find methadone OTPs, SAMHSA's treatment locator at findtreatment.gov includes searchable OTP listings. SAMHSA's National Helpline (1-800-662-4357) can also provide referrals.

Related: Types of Addiction Treatment · Opioid Addiction & Mental Health · Insurance Coverage for MAT