Understanding naltrexone treatment for opioid addiction
If you are researching naltrexone treatment for opioid addiction, you are likely looking for a way to stay off opioids after you have already gone through withdrawal. Naltrexone is different from medications like Suboxone or buprenorphine. It does not replace opioids in your system and it does not produce any kind of high. Instead, it blocks the effects of opioids and helps you protect your recovery once you are opioid free.
Naltrexone is one of several options available in an evidence based opioid treatment plan. Understanding how it works, who it is for, and how it fits into an outpatient program can help you decide if this approach is right for you.
What naltrexone is and how it works
Naltrexone is a medication that is FDA approved to help you maintain recovery from opioid use disorder and alcohol use disorder. It is considered an opioid antagonist, which means it attaches to the same receptors in your brain that opioids use, but it does not activate them.
Instead of producing a high, naltrexone blocks the euphoric and sedative effects of opioids such as heroin, morphine, and codeine. This blocking effect reduces the rewarding feelings if you try to use opioids, and it helps decrease cravings over time [1]. Because naltrexone does not produce opioid like effects and does not cause mental or physical dependence, it is considered non addictive [2].
You can receive naltrexone in two main forms. One is a daily oral tablet, commonly 50 mg, that you swallow each day. The other is an extended release intramuscular injection, often known by the brand Vivitrol, which you receive once a month in a clinic setting [3].
Naltrexone vs Suboxone and buprenorphine
When you look at medication options in an outpatient MAT program, you will often see three main choices for opioid use disorder: buprenorphine (often prescribed as Suboxone), methadone, and naltrexone. Each works in a different way and fits different needs.
Buprenorphine, provided through a suboxone treatment clinic or buprenorphine treatment program, is a partial opioid agonist. It activates opioid receptors just enough to prevent withdrawal and cravings but not enough to create a strong high when taken as prescribed. Methadone is a full opioid agonist that is carefully dosed in specialized clinics. Both are considered replacement therapies and are very effective for many people.
Naltrexone is different. It is a pure antagonist, so it blocks opioid receptors instead of activating them. You must be completely off opioids for 7 to 10 days, and often longer for long acting opioids, before starting naltrexone, or you risk going into sudden withdrawal [4].
Extended release naltrexone has been shown to be about as effective as buprenorphine for many patients with heroin and prescription opioid addiction when started after withdrawal is complete [5]. Some treatment centers also view extended release naltrexone and buprenorphine as safer long term options than methadone for people seeking abstinence based recovery and more flexible care settings [6].
In a clinical opioid addiction treatment plan, your team will help you compare these medications based on your history, current opioid use, medical status, and recovery goals. You do not have to make this decision alone.
When naltrexone is used in opioid recovery
Naltrexone is most often used after you have already gone through detox and are medically stable. It is designed to help you remain drug free and maintain the progress you have made. It is not a medication for active withdrawal and it is not appropriate if you are still using opioids heavily.
You may be a candidate for naltrexone if:
- You have completed opioid withdrawal, including from fentanyl, heroin, or pain medications
- You want a non addictive medication that does not produce any opioid effect
- You prefer a once monthly injection or a daily pill with no controlled substance status
- You are motivated to stay in counseling, groups, and a structured program
Naltrexone is often integrated into a medication assisted treatment program that includes counseling, behavioral therapies, and ongoing recovery support. Federal guidance emphasizes that naltrexone should always be part of a comprehensive treatment plan, not used as a stand alone solution [7].
Requirements before starting naltrexone
One of the most important parts of naltrexone treatment for opioid addiction is the preparation phase. You must be completely opioid free before starting. If you still have opioids in your system, naltrexone can trigger rapid and severe withdrawal, called precipitated withdrawal.
Clinical guidelines generally recommend that you:
- Wait at least 7 to 10 days after your last use of short acting opioids
- Wait 10 to 14 days after long acting opioids
- Have your opioid free status confirmed through a naloxone challenge or urine drug tests when appropriate [8]
If you are currently using fentanyl or other strong opioids, your team may recommend a supervised taper, an opioid withdrawal treatment with medication, or a short stay in a fentanyl detox outpatient program or higher level of care to get you safely through withdrawal before starting naltrexone.
During this time, your providers will also review your medical history, including liver health, mental health symptoms, and any other medications you take. High doses of naltrexone may cause liver damage in some people, so you will likely have baseline blood tests before starting and regular monitoring after, especially if you have a history of hepatitis or other liver conditions [9].
How naltrexone is given in outpatient MAT
In a structured outpatient opioid treatment program or mat clinic for opioid use disorder, naltrexone can be delivered in ways that support your schedule and daily responsibilities while maintaining clinical oversight.
Oral naltrexone
The tablet form of naltrexone is usually taken once daily at home. In some clinic or treatment center settings, doses may be supervised every day, every other day, or every third day depending on the plan that you and your provider agree on [10]. Daily pills can be a good fit if you prefer flexibility and are comfortable with taking a medication every day.
Extended release injection
Extended release naltrexone is given as a 380 mg intramuscular injection, usually into the buttock, once every 4 weeks by a licensed practitioner. It slowly releases medication over the month, which eliminates daily dosing decisions and can help reduce the risk of missed doses or sudden relapse [3].
Many people find that combining extended release naltrexone with a structured outpatient opioid treatment schedule, weekly therapy, and support groups creates a predictable foundation for early recovery.
Benefits and effectiveness of naltrexone
When you use naltrexone as part of an opioid addiction medication treatment plan, you may experience several key benefits.
First, naltrexone blocks the high from opioids. If you slip and use opioids while on naltrexone, you are unlikely to feel the same euphoria you remember. Over time, this can weaken the association between opioids and reward in your brain, which supports long term change [4].
Second, naltrexone helps reduce cravings for many people. By occupying opioid receptors without activating them, it can stabilize your brain chemistry enough for you to focus more fully on counseling, work, family, and rebuilding your life [1].
Third, extended release naltrexone appears to reduce relapse and overdose risk when it is combined with evidence based therapies and peer support. Programs that integrate naltrexone into broader recovery models report high engagement, strong medication adherence, and meaningful abstinence rates over the first six months of treatment [6].
Finally, because naltrexone is not a controlled substance and has no abuse potential, it can be easier to manage in regular medical offices and community clinics. You may not need to attend specialized methadone clinics or daily dosing centers, which can make your medication assisted recovery program more convenient [6].
Risks, side effects, and safety warnings
Like all medications, naltrexone has potential risks and side effects. Knowing about them in advance can help you and your team respond quickly if something is not right.
Common side effects may include nausea, headache, fatigue, trouble sleeping, or anxiety, especially in the first few days. Many of these symptoms improve as your body adjusts. However, there are also more serious concerns to keep in mind.
One key safety warning is overdose risk if you stop naltrexone and then return to opioid use. Naltrexone treatment can reduce your tolerance to opioids. This means that if you relapse, the same dose you used before, or even a lower dose, can suddenly be enough to cause life threatening overdose, respiratory arrest, or circulatory collapse [3]. Using opioids to try to overcome the blocking effect while you are on naltrexone can also lead to overdose, coma, or death [2].
Another concern is liver health. Large doses of naltrexone may cause liver damage. You should tell your provider if you have a history of hepatitis or liver disease, and you should seek medical attention right away if you notice symptoms such as unusual tiredness, dark urine, yellowing of the skin or eyes, or unusual bleeding or bruising [10].
Regular medical monitoring, including periodic blood tests, is an essential part of safe naltrexone treatment. Your providers will also watch for mood changes, irritability, or any signs of suicidal thinking, so it is important to report emotional shifts honestly during appointments [2].
Naltrexone is non addictive and does not cause withdrawal when stopped, but decisions about starting, continuing, or discontinuing treatment should always be made with your care team.
Integrating naltrexone with therapy and support
Naltrexone can be a powerful tool, but medication alone is rarely enough to rebuild a life. The most effective naltrexone treatment for opioid addiction takes place within a comprehensive program that includes counseling, behavioral therapies, and peer support.
In a dual diagnosis MAT program, you can address both substance use and co occurring mental health conditions like depression, anxiety, or PTSD. This whole person approach is important because untreated mental health symptoms are a common trigger for relapse.
Your plan might include:
- Individual therapy focused on coping skills, triggers, and relapse prevention
- Group therapy where you can share experiences with others facing similar challenges
- Family sessions to rebuild trust and improve communication
- Skills training, such as emotional regulation, stress management, and healthy routines
Federal agencies emphasize that naltrexone must be combined with counseling and social support to be effective in preventing relapse, rather than being used alone [11]. A well designed opioid relapse prevention program will weave medication, therapy, and community together so that you are not relying on any one piece in isolation.
Insurance coverage and access to care
Cost is a real concern when you are considering any medication assisted treatment program. Many commercial health plans and public insurance options now cover naltrexone, especially the oral form, when it is used as part of treatment for opioid use disorder. Extended release injections may require prior authorization or specific documentation of medical necessity.
When you connect with an insurance covered MAT program, the admissions or benefits team can help verify your coverage, explain copays or deductibles, and outline any steps needed to approve naltrexone. Clinics that focus on MAT for long term recovery are often familiar with these processes and can guide you through them.
If transportation or scheduling is challenging, look for an outpatient MAT program that offers evening hours, telehealth visits for counseling, and coordinated appointment times for injections, lab work, and groups. The goal is to fit treatment into your life in a sustainable way.
Naltrexone and fentanyl addiction
If you are struggling with fentanyl, you may already know that detox and early recovery can be especially difficult. Fentanyl is potent and long lasting, and it can be present in other street drugs without your knowledge. Naltrexone can still be part of a fentanyl addiction treatment program, but timing and supervision become even more important.
Your team may first recommend a period of stabilization using other medications in a suboxone therapy program or a short term opioid withdrawal treatment with medication. Only after you have been fully free from fentanyl for a longer window, confirmed through testing and clinical assessment, would naltrexone be considered.
Because relapse to fentanyl after a period on naltrexone carries a very high overdose risk, you and your providers will spend time building a detailed safety and relapse prevention plan, including overdose education and access to naloxone. A well structured clinical opioid addiction treatment program will address these risks openly and give you concrete tools to stay safe.
How long you may stay on naltrexone
There is no single correct length of time to stay on naltrexone. Some people use it for several months to a year, while others benefit from longer courses. You and your care team will revisit this question regularly, based on your progress, stability, and preferences.
In the early months, naltrexone can function as a strong safety net while you build habits, relationships, and routines that support your recovery. Over time, as you gain confidence and your life becomes more stable, you may choose to continue or taper off under medical supervision.
Organizations specializing in MAT emphasize that decisions about duration should be collaborative and individualized. Your team will consider factors like your cravings, stress level, environment, mental health, and past relapse history when you discuss changes to your plan [6].
Frequently asked questions about naltrexone treatment
Will naltrexone help with withdrawal?
No. Naltrexone is not used to treat active opioid withdrawal and can actually make withdrawal much worse if you still have opioids in your system. If you are still using or you are in early withdrawal, you may need a separate opioid withdrawal treatment with medication before you can safely start naltrexone [10].
Can you drink alcohol on naltrexone?
Naltrexone is also approved for alcohol use disorder and can reduce cravings for alcohol, but it does not give you permission to drink safely. If you have both alcohol and opioid use concerns, your providers will help you design a plan that addresses both and will clearly explain any alcohol related guidelines for your treatment [10].
Is naltrexone right for you if you are still using opioids?
Naltrexone is not recommended if you are still using street opioids or taking large amounts of prescribed opioids. It will not relieve withdrawal, and it can worsen symptoms if started too soon after your last use [10]. If you are still using, a suboxone treatment clinic or another form of clinical opioid addiction treatment might be a better first step, with the option of naltrexone later.
What if you miss a dose or an injection?
If you miss a pill, you should contact your prescriber for guidance rather than doubling up without instructions. If you miss a scheduled injection, it is important to reschedule as soon as possible, and you should not assume you are fully protected from relapse risk. Staying in close touch with your team and your outpatient opioid treatment program can help you navigate any gaps in dosing safely.
Taking your next step toward recovery
Naltrexone treatment for opioid addiction is not a quick fix, but it can be a powerful part of a comprehensive plan that includes counseling, medical care, and consistent support. If you are already opioid free and looking for a way to protect your progress, naltrexone may provide the additional layer of safety you need to focus on rebuilding your life.
You do not have to figure this out on your own. An experienced medication assisted recovery program can help you compare naltrexone, buprenorphine, and other options, confirm your medical readiness, and design a schedule that fits your work, family, and financial situation.
Reaching out to an outpatient MAT program or mat clinic for opioid use disorder is a strong and practical step toward long term change. With the right combination of medication, therapy, and support, you can build a recovery that lasts.
References
- (SAMHSA)
- (Mayo Clinic)
- (SAMHSA, University of Arkansas for Medical Sciences)
- (Mayo Clinic, SAMHSA)
- (University of Arkansas for Medical Sciences)
- (Hazelden Betty Ford Foundation)
- (SAMHSA, MedlinePlus)
- (Mayo Clinic, SAMHSA, University of Arkansas for Medical Sciences)
- (MedlinePlus, Mayo Clinic)
- (MedlinePlus)
- (MedlinePlus, SAMHSA)