Medication-Assisted Treatment (MAT): What It Is and What the Evidence Shows

What Is Medication-Assisted Treatment?

Medication-assisted treatment (MAT) is the use of FDA-approved medications, in combination with counseling and behavioral therapies, to treat substance use disorders. MAT is currently available for opioid use disorder, alcohol use disorder, and nicotine dependence. It is one of the most evidence-based approaches to addiction treatment, with multiple large-scale studies demonstrating its effectiveness in reducing substance use, preventing overdose, and improving long-term recovery outcomes.

Despite this evidence, MAT remains controversial in some recovery communities, particularly those with strong 12-step traditions. Some members of these communities view the use of medications as inconsistent with "true" sobriety. This view is not supported by the official positions of AA or NA, both of which explicitly support the use of medications prescribed by physicians, and it is not supported by the scientific evidence. MAT saves lives, and the stigma surrounding it costs lives.

The World Health Organization lists methadone and buprenorphine on its List of Essential Medicines — a designation reserved for medications that are considered indispensable to meeting the basic health needs of a population. This recognition reflects the overwhelming evidence that these medications are not merely helpful but essential for addressing the global burden of opioid use disorder.

MAT for Opioid Use Disorder

Three medications are FDA-approved for the treatment of opioid use disorder: methadone, buprenorphine, and naltrexone. Each works through a different mechanism and is appropriate for different patients and circumstances.

Methadone is a long-acting opioid agonist that reduces cravings and prevents withdrawal without producing the euphoria associated with shorter-acting opioids. It has been used in the treatment of opioid use disorder since the 1960s and has one of the strongest evidence bases of any addiction treatment. Methadone must be dispensed through federally regulated opioid treatment programs (OTPs) and is typically taken daily under supervision, at least initially. Research consistently shows that methadone treatment reduces illicit opioid use, reduces overdose mortality by 50 percent or more, reduces criminal activity, and improves social functioning. The requirement for daily clinic attendance can be a barrier for some patients, but it also provides a structured point of contact with healthcare and social services.

Buprenorphine is a partial opioid agonist that reduces cravings and withdrawal symptoms. Because it is a partial agonist rather than a full agonist, it has a "ceiling effect" — above a certain dose, increasing the dose does not increase the opioid effect, which reduces the risk of overdose. Buprenorphine is available in several formulations, including sublingual tablets and films (Suboxone, which combines buprenorphine with naloxone to deter misuse) and a monthly injectable formulation (Sublocade). Buprenorphine can be prescribed by certified physicians in office-based settings, making it significantly more accessible than methadone. Research consistently shows that buprenorphine treatment is associated with significant reductions in opioid use, overdose risk, and mortality. The development of long-acting injectable formulations has further improved adherence and outcomes by eliminating the need for daily dosing.

Naltrexone is an opioid antagonist that blocks the effects of opioids, eliminating the reward associated with opioid use. It is available as a daily oral tablet (ReVia) or a monthly injectable formulation (Vivitrol). Unlike methadone and buprenorphine, naltrexone has no abuse potential and does not require special certification to prescribe. However, it requires complete detoxification from opioids before initiation — typically at least 7–10 days for short-acting opioids and longer for methadone — which can be a significant barrier to treatment. Naltrexone is particularly useful for patients who are highly motivated to achieve abstinence and who have successfully completed detoxification, and for patients in settings where controlled substances cannot be prescribed.

MAT for Alcohol Use Disorder

Three medications are FDA-approved for the treatment of alcohol use disorder: naltrexone, acamprosate, and disulfiram. Despite the availability of these effective medications, they are dramatically underutilized — studies suggest that fewer than 10 percent of people with alcohol use disorder who could benefit from medication receive it.

Naltrexone (the same medication used for opioid use disorder) reduces the rewarding effects of alcohol by blocking opioid receptors in the brain's reward system. Alcohol produces some of its pleasurable effects indirectly through the opioid system, and naltrexone blunts this effect, reducing the urge to drink and the pleasure derived from drinking. Multiple large randomized controlled trials have shown that naltrexone reduces heavy drinking days and increases abstinence rates. It is available as a daily oral tablet or a monthly injectable formulation (Vivitrol), which improves adherence by eliminating the need for daily dosing.

Acamprosate reduces the neurological symptoms of protracted alcohol withdrawal — the anxiety, insomnia, and dysphoria that can persist for months after stopping drinking and that are major drivers of relapse. It works by modulating glutamate and GABA neurotransmitter systems that are dysregulated by chronic alcohol use. Acamprosate is most effective for people who have already achieved abstinence and want to maintain it, and it is particularly useful for patients who experience significant anxiety and sleep disturbance in early recovery.

Disulfiram (Antabuse) works by blocking the metabolism of alcohol, causing an unpleasant reaction — flushing, nausea, vomiting, rapid heartbeat — when alcohol is consumed. It is a deterrent rather than a craving-reducing medication, and its effectiveness depends heavily on the person's motivation to take it consistently. Disulfiram is most effective when taken under supervision — for example, by a family member or healthcare provider — which ensures adherence and maximizes its deterrent effect.

The Evidence for MAT

The evidence for MAT is extensive and compelling. Decades of research across multiple countries and populations have consistently demonstrated its effectiveness. Key findings include:

• Buprenorphine and methadone treatment for opioid use disorder reduce mortality by 50 percent or more compared to no treatment — one of the largest mortality reductions of any medical intervention.
• Naltrexone for alcohol use disorder reduces heavy drinking days by approximately 25 percent compared to placebo and significantly increases rates of abstinence.
• People receiving MAT are more likely to remain in treatment, more likely to achieve abstinence, and more likely to maintain employment and stable housing than people receiving behavioral treatment alone.
• MAT reduces the transmission of HIV and hepatitis C by reducing injection drug use — a public health benefit that extends far beyond the individual patient.
• The combination of MAT with behavioral therapy and peer support produces better outcomes than any single approach alone.

Barriers to MAT Access

Despite the overwhelming evidence for MAT's effectiveness, significant barriers prevent many people from accessing it. These barriers include stigma — both from the general public and from within recovery communities — that frames MAT as "not real sobriety." They also include regulatory barriers, particularly for methadone, which can only be dispensed through federally regulated clinics that are often located in urban areas and require daily attendance. Geographic barriers are significant in rural areas, where there may be no MAT providers within a reasonable distance. Cost and insurance coverage are barriers for many patients. And provider shortages — there are not enough physicians trained and certified to prescribe buprenorphine — limit access in many communities.

Addressing these barriers requires policy changes, increased training for healthcare providers, expanded insurance coverage, and a cultural shift in how recovery communities understand and accept MAT. The lives at stake make this work urgent.

MAT and the 12-Step Program

The relationship between MAT and the 12-step program has been complicated, but it is evolving. The official positions of both AA and NA support the use of medications prescribed by physicians, and many people successfully combine MAT with 12-step participation. Some 12-step groups are more welcoming of people on MAT than others, and people on MAT may need to seek out groups that are explicitly supportive of medication use.

The most important thing to understand is that MAT and the 12-step program are not mutually exclusive. They address different dimensions of addiction — MAT addresses the neurobiological dimension, while the 12-step program addresses the psychological, social, and spiritual dimensions. For many people, the combination of MAT and 12-step participation produces better outcomes than either alone. The goal is recovery — a full, meaningful life free from the domination of addiction — and all evidence-based tools that support that goal deserve to be embraced.

Starting MAT: What to Expect

For people considering MAT, the first step is a conversation with a healthcare provider who specializes in addiction medicine. This conversation should include a thorough assessment of the substance use disorder, any co-occurring medical or mental health conditions, and the patient's goals and preferences. The provider will recommend the most appropriate medication based on this assessment and will explain what to expect from treatment.

Starting MAT is not a sign of weakness or failure — it is a sign of courage and commitment to recovery. The medications used in MAT are tools, like any other medical tool, that help the brain heal from the damage of addiction and give the person the stability they need to do the psychological and spiritual work of recovery. For many people, MAT is the bridge that makes recovery possible.