One naltrexone injection vs oral form is not right for every person. Your daily habits and health history matter. This guide covers both forms for alcohol use disorder. See our guide to medications for alcohol use disorder for other options.
Our editorial team looks into public health sources. We do not provide treatment. Do not rely on this guide to begin or end medication. Talk to a doctor about side effects and which form fits you.
Two Ways to Take Naltrexone for Alcohol Use Disorder
When you weigh naltrexone injection vs oral choices, you are looking at the same medicine in two formats. Both hold naltrexone. Yet they enter your body differently. One is a pill you swallow every day at home. The other is a shot given by a healthcare provider once a month.[1]
In the brain, naltrexone blocks opioid receptors. It can help some people cut back or stop by lowering the feeling of a high from drinking. It is one tool in a larger plan. Counseling and support groups are often part of that plan.
This guide covers only alcohol use disorder. It does not pull from opioid use disorder studies to say one form beats the other for alcohol. To learn more about how naltrexone works, read our guide on how naltrexone works.
Naltrexone Injection vs Oral: How the Two Forms Differ
Your life decides whether you pick the daily pill or the monthly shot. The goal is the same: reduce cravings for alcohol. The routine is where they differ the most.
Once daily
oral naltrexone is taken by mouth as prescribed[2]
Every 4 weeks
extended-release injectable naltrexone is given by a healthcare professional[3]
Naltrexone Shot vs Pill: Side-by-Side Look
The table below compares the practical sides of each choice. It does not say one is better than the other. What feels convenient varies by person. Your schedule, access to care, and habits all play a part.
| Feature | Oral Naltrexone | Extended-Release Injectable Naltrexone |
|---|---|---|
| Route & Routine | Taken by mouth once daily as prescribed[2] | Administered by a healthcare professional once every four weeks[3] |
| Practical Advantages | No clinic visits needed; can be taken at home[2] | Removes the need for daily reminders; ensures consistent delivery[3] |
| Ask Your Clinician | "How can I build a habit to remember my daily dose?" | "Do I need to travel far for my injection appointments?" |
Ask yourself what gets in the way of keeping a plan. The monthly rhythm might help if you tend to forget pills. If you dislike needles or clinics, the pill might fit better. Take these questions to your doctor. They can help you find the best match.
Before starting naltrexone, your clinician reviews any current or recent opioid use. They decide how long you need to stay opioid-free. Ask your clinician how this safety check applies to you.
Details on the Monthly Injection Schedule
Each dose of the monthly naltrexone injection requires a trip to a provider.[3] You need reliable access to a clinic that provides this service. The injection delivers the medicine, but it does not replace ongoing care. You will still have follow-up visits to discuss progress. For a broader look at medication and counseling for AUD, see our guide to mat for alcohol use disorder.
Start
Discuss options with your clinician and choose a formulation that fits your lifestyle.
Routine
Follow the prescribed plan, whether that is taking a pill daily or attending an injection visit every four weeks.[2][3]
Follow-up
Return for regular check-ins to review how you are doing and adjust support if needed.
This timeline shows the typical flow of care. It is not a dosing instruction or a treatment protocol. Your doctor's advice and your own needs decide your actual schedule.
Is the Monthly Naltrexone Shot More Effective?
People with alcohol use disorder can find help from either naltrexone form. Researchers have tested each form separately against a placebo, and there is also direct evidence comparing them. The XON trial is a head-to-head study that compared the monthly naltrexone injection to the daily pill. Yet, current direct evidence does not show that one formulation is better than the other.
For the daily pill, an AHRQ evidence review found that oral naltrexone reduces the risk of returning to heavy drinking compared with placebo.[4] This means taking the medication can help keep heavy drinking days lower than a sugar pill.
A separate 24-week randomized trial used extended-release injectable naltrexone. It lowered heavy-drinking days versus placebo. This held for patients who stopped drinking a week before starting.[5] These studies track different results. They do not reveal which form works better.
The American Psychiatric Association finds limited evidence. This is when comparing long-acting injectable naltrexone to oral forms.[6] They suggest it may boost adherence.[6] One shot lasts a month. This skips the need to recall a daily dose. That may help if you lack consistency. Ask your doctor which choice suits your life and goals.
Keeping Opioid and Alcohol Withdrawal Safe
Share any current or past opioid use with your healthcare provider. This includes prescription pain medicines. Do this before starting naltrexone.
Naltrexone blocks opioid effects, which can interfere with opioid-containing pain medicines and pain management.[7] If you have surgery or need pain care, your clinician must know you take naltrexone. They can adjust your pain plan to keep you safe.
A clinician decides how long you must be opioid-free before starting naltrexone. Do not judge your own readiness. A clinician must confirm it is safe to begin treatment.[7]
Acute alcohol withdrawal is not treated by naltrexone. If you drink heavily, do not stop at home. Get safe medical help from a doctor or a treatment program.
As naltrexone’s opioid blockade wanes or after treatment ends, reduced opioid tolerance can increase overdose risk if a person returns to opioid use.[8] This is a serious safety issue for your care team to address. Read our guide on naltrexone and opioid safety for more details.
If you suspect an overdose, call 911 or go to the nearest emergency room immediately.
Side Effects: Signs to Watch and People to Call
Naltrexone injection vs oral options both carry risks of side effects.[8][7] The pill and the shot may cause different problems.[8][7] Learning what is normal helps you spot when to reach out to your doctor.
For the daily pill, commonly reported side effects include nausea, headache, dizziness, and tiredness.[8] Nausea and injection-site reactions have been reported with the monthly injection.[7] Severe injection-site reactions have also been reported and may need medical care or even surgery.[7]
Call your prescriber if you feel odd or sick. Always speak with your prescriber before altering your medication.
If you notice signs or symptoms of acute hepatitis, get medical help right away.
Keeping track of these changes can be tough. You are not alone in this. Our guide on managing medication side effects gives tips for logging symptoms. It also helps you ready yourself for chats with your care team. Stay connected with your prescriber. They can help decide if your plan needs updates.
Making a Choice and Reviewing Insurance
Deciding between a monthly shot and a daily pill is up to you. Your habits, health background, and insurance matter. Use the tools below to get ready for a talk with your prescriber.
Is Naltrexone Similar to Ozempic? Do Doctors Avoid It?
Naltrexone is not the same as Ozempic. Naltrexone works as an opioid antagonist.[8] Ozempic contains semaglutide, which is a different class of drug. They act in different ways. You cannot exchange one for the other.
Some folks fear that doctors do not like naltrexone. This belief is incorrect. Key guidelines name naltrexone a standard choice for alcohol use disorder.[6] It suits patients who are a good match.[6] Your doctor’s advice rests on your unique health needs. If the idea of a formal evaluation feels daunting, our guide to alcohol use disorder diagnosis walks through what to expect.
What Should You Discuss With a Clinician?
This self-check is for information only and isn't a diagnosis. It helps you prepare questions for your care team.
Questions to Take to a Clinician and Insurer
Your ticks are saved on this device only.
Check your specific benefits with your plan. For more details on how plans handle these medications, see our guide on naltrexone insurance coverage.
Frequently Asked Questions
What is the most effective way to take naltrexone for alcohol use disorder?
No single form is best for everyone. Evidence is limited when comparing the shot to the pill. The shot may help people stick to their plan better.[6] Talk to a clinician about your routine and health.
How long does a naltrexone injection last?
A healthcare professional gives the shot once every four weeks.[3] You do not take a pill every day. Ask your prescriber how this schedule fits your life.
Does the injection work better than the pill for alcohol use disorder?
We do not know if the shot works better than the pill. Evidence is limited for alcohol use disorder.[6] Do not mix up results from other conditions.
Why might I feel unusual or unwell while taking naltrexone?
Common side effects of the pill include nausea, headache, dizziness, and tiredness.[8] The shot can cause nausea and soreness at the injection site.[7] For non-emergency side effects, contact your prescriber. For signs of an overdose, seizures, severe confusion, hallucinations, a high fever or racing heart during withdrawal, call 911 or go to the nearest emergency room now. For thoughts of suicide or self-harm, call 911 or go to the nearest emergency room now; you can also call or text 988.
Is naltrexone like Ozempic?
No, they are different medicines. Naltrexone is an opioid antagonist.[8] Do not use Ozempic info to answer questions about naltrexone.
Why don’t doctors like naltrexone?
Doctors do not dislike naltrexone. It is a standard option for alcohol use disorder.[6] Your clinician picks the best fit for your health history.
Can oral naltrexone be started while someone is still drinking?
The APA guidance cited here does not state that someone must stop drinking before starting oral naltrexone. For people with alcohol use disorder and co-occurring opioid use disorder, it includes those who want to abstain from opioids and either abstain from or reduce alcohol use, provided they can abstain from opioids for an appropriate time before starting naltrexone.[6] In a 24-week injection trial, a subset who abstained from drinking during the week before their first dose had reduced heavy-drinking days compared with placebo; this finding does not establish an abstinence requirement for starting the injection or the pill.[5] Ask your clinician whether and when to start based on your situation.
