Naltrexone is a non-addictive, FDA-approved medication that helps many people with alcohol use disorder (AUD) drink less by reducing cravings and blunting the pleasurable reward of alcohol. It comes in two forms: a daily pill (oral naltrexone) and a once-monthly injection known by the brand name Vivitrol. It is not a cure, and it works best as one part of a broader treatment plan. This chapter of our guide to alcohol addiction explains how these medications work so you can have an informed conversation with a provider. To start with support, Northwoods Haven offers outpatient alcohol treatment in Minnesota for adults across the Twin Cities.
What Is Naltrexone?
Naltrexone is a prescription medicine approved by the U.S. Food and Drug Administration to treat alcohol use disorder (AUD), a condition also called alcohol dependence. According to the Substance Abuse and Mental Health Services Administration (SAMHSA), naltrexone is available as an oral pill for AUD and as an extended-release intramuscular injection [1]. As a treatment for alcohol dependence, naltrexone is non-narcotic and is not a controlled substance.
| Form | How it is taken | Notes |
|---|---|---|
| Oral naltrexone | A pill, usually once daily | Flexible; can be stopped quickly if a provider advises |
| Extended-release injectable (Vivitrol) | One injection about every four weeks, given by a provider | Removes the need to remember a daily pill [2] |
The FDA notes that Vivitrol is a prescription injectable medicine used to treat alcohol dependence [3]. A medical provider can help you weigh which form fits your needs, health history, and daily routine.
How Naltrexone Works for Alcohol Use Disorder
When a person drinks, alcohol triggers the release of natural feel-good chemicals in the brain that reinforce the urge to keep drinking. Naltrexone interrupts that loop. SAMHSA explains that naltrexone blocks opiate receptors that are involved in the rewarding effects of drinking and craving for alcohol [4]. By quieting alcohol’s reward signal, naltrexone can make drinking feel less rewarding and reduce the cravings that so often drive a return to heavy use.
Importantly, naltrexone is an opioid antagonist, which is a blocker, not an opioid. It does not produce a high and is not the kind of medication that leads to physical dependence [4].
Oral Naltrexone vs. Vivitrol
Both forms contain the same active medication and work the same way in the brain. The main differences are practical. The monthly injection removes the need to remember a daily pill, which some people find helpful for staying on track. The daily pill offers more flexibility and can be stopped quickly if a provider recommends a change. Coverage and cost vary; Northwoods Haven accepts Medicaid and Blue Cross Blue Shield, and a medical provider or your plan can clarify what is covered for you.
There is no single better option, only the one that fits your circumstances. That is exactly the kind of trade-off to discuss during a comprehensive assessment and with your prescriber.
How Effective Is It?
Naltrexone is one of the most-studied medications for AUD. The honest answer is that it helps many people, but it is not a guarantee, and it is not a standalone fix.
The large, federally funded COMBINE study found that patients who received naltrexone along with structured medical management had a higher percentage of days abstinent than those receiving medical management only, and that naltrexone reduced the risk of a heavy drinking day [5]. In other words, the benefit showed up most clearly when the medication was paired with counseling and support, not when it was used alone. For most patients, naltrexone works best alongside counseling.
That is the key takeaway: SAMHSA advises that medications for AUD should be prescribed as part of a comprehensive treatment approach that includes counseling and other psychosocial therapies [4]. Medication can lower the volume on cravings; the counseling, skills, and structure you build in treatment help you use that opening.
Common Side Effects and Who Should Not Take It
Like any medication, naltrexone can cause side effects. SAMHSA reports that the most common are nausea and vomiting, with less common effects including diarrhea, constipation, joint or muscle pain, insomnia, and headache [4]. Most side effects are manageable, and your provider can talk you through what to expect.
There is one safety point that matters for everyone considering naltrexone: it should not be taken by anyone currently using or dependent on opioids or other opioid drugs. SAMHSA states that naltrexone is contraindicated in patients currently dependent on opioids, including those being maintained on opioid agonists such as methadone or buprenorphine, because it can trigger sudden, severe withdrawal symptoms [4]. Guidance for the injectable form generally recommends being opioid-free for 7 to 10 days before starting, and a provider may use urine testing and, in some situations, a naloxone challenge to help assess whether it is safe to begin naltrexone. Neither test can completely eliminate the risk of precipitated withdrawal. [2].
This is not something to sort out on your own. Only a qualified healthcare provider can review your full health history, including other medications, liver health and liver function, and pregnancy status, and determine whether naltrexone is safe and appropriate for you. Your provider may also start at a lower dose to reduce side effects.
How Medication Fits Into Outpatient Treatment
Northwoods Haven is an outpatient provider offering an intensive outpatient program (IOP) and continuing care for adults 18 and older. We are not a detox, inpatient, or residential program, and we do not prescribe medication. What we do is help you build a plan, and part of a strong plan is understanding whether a medication conversation belongs in it.
- Start with an assessment. A comprehensive assessment helps determine the right level of care and whether medication is worth discussing with a provider.
- Talk with a medical provider. Any decision about naltrexone, Vivitrol, or other medications is a medical one, made with a prescriber who knows your history.
- Combine medication with support. If you and your healthcare provider choose medication, our outpatient programming provides the counseling and structure that research shows helps medication work best. For many people, medication can be combined with counseling, medical follow-up, and recovery support as part of an individualized treatment plan.
If you want to understand the condition more deeply, our overview of alcohol use disorder is a good next read, along with our chapter on how much alcohol is too much. Because heavy, long-term drinking carries other health risks, you may also want to learn about alcoholic liver disease and wet brain (Wernicke-Korsakoff syndrome). If you are physically dependent on alcohol, do not stop drinking suddenly on your own, because withdrawal can be dangerous; see our chapter on delirium tremens.
Other FDA-Approved Options
Naltrexone is not the only medication approved for AUD. SAMHSA also describes acamprosate, which helps support ongoing abstinence, and disulfiram, which causes an unpleasant reaction if a person drinks alcohol [4]. Each works differently and suits different people. We mention them so you know your options are broader than one medication, but which, if any, is right for you is a decision for a medical provider.
Naltrexone and Vivitrol Frequently Asked Questions
Do you have to stop drinking before starting naltrexone?
It depends on the form. Oral naltrexone can sometimes be started while a person is still drinking, although a provider may recommend a period of abstinence depending on the person’s health and treatment goals. Vivitrol is different: FDA labeling states that patients should be able to abstain before treatment and should not be actively drinking when the first injection is given. Both forms also require careful screening for recent opioid use. Your provider will advise what is right for you.
Does naltrexone stop you from getting drunk?
No. Naltrexone reduces the rewarding, pleasurable effects of alcohol and lowers cravings [4]. It does not prevent intoxication or impairment, so it is not a green light to drink.
How long do you take it?
It varies from person to person. There is no one-size-fits-all timeline, and how long to continue is a decision you make with your prescriber based on your progress and goals.
Is naltrexone addictive?
No. Naltrexone is an opioid blocker (antagonist), not an opioid [4]. It does not produce a high and is not habit-forming.
Sources
- Substance Abuse and Mental Health Services Administration (SAMHSA), Naltrexone: https://www.samhsa.gov/substance-use/treatment/options/naltrexone
- SAMHSA, TIP 49, Chapter 5: Extended-Release Injectable Naltrexone: https://www.ncbi.nlm.nih.gov/books/NBK64031/
- U.S. Food and Drug Administration (FDA), Naltrexone for Extended-Release Injectable Suspension (Vivitrol) Information: https://www.accessdata.fda.gov/drugsatfda_docs/label/2015/021897s029lbl.pdf
- SAMHSA, Medication for the Treatment of Alcohol Use Disorder: A Brief Guide: https://library.samhsa.gov/sites/default/files/sma15-4907.pdf
- National Institute on Alcohol Abuse and Alcoholism (NIAAA), COMBINE Study: https://www.niaaa.nih.gov/research/data-archive-resources/niaaa-controlled-datasets/combine-study
