Key Points
- Vivitrol is an injectable form of naltrexone used as an opioid antagonist to help individuals recover from alcohol dependence and prevent a return to opioid use after detoxification.
- Most patients experience mild to moderate side effects such as nausea, headaches, and dizziness that typically resolve within a few days to two weeks after the initial injection.
- While rare, serious risks include liver damage, severe injection-site reactions, and intense withdrawal symptoms if opioids are still present in the body at the time of the injection.
- Ongoing clinical monitoring of vital signs, mood changes, and liver health is essential during the first month of treatment to ensure the medication is being tolerated safely.
- Comprehensive recovery programs like New Wave Recovery Center combine medication-assisted treatment with evidence-based therapies to provide holistic support throughout the recovery process.
Vivitrol is an injectable form of naltrexone that can be used to help (1) people recover from alcohol dependence and (2) avoid returning to opioid use after detoxification.[1,2] Starting Vivitrol may raise questions about its side effects.
The objective of this article is to assist the client with a detailed, factual understanding of naltrexone’s side effects. It will cover common side effects, as well as serious side effects.
The information provided in this article is intended for educational use only. It is not a substitute for personal medical advice provided by your licensed healthcare provider, who is familiar with your individual medical history.
What Vivitrol Does and Why People Experience Side Effects
Vivitrol is the brand name for naltrexone, which is an opioid antagonist. This means that it blocks opioid receptors in the brain and body and reduces the pleasurable effects of opioids and alcohol [1]. Naltrexone is not the “cure” for addiction to opioids or alcohol and is considered to be more effective when combined with therapy and support services for recovery.
Because naltrexone interacts with how the brain and body’s opioid receptors respond to substances, some people will have physical or emotional reactions as they adjust to using this medication [2].
Unlike some medications people worry about, naltrexone is not habit-forming, though it is worth knowing which drugs do carry that risk, such as when people ask whether methocarbamol is addictive.
Why Vivitrol Side Effects Vary from Person To Person
Not all people will have the same experience when taking naltrexone. The variables affecting how each person experiences side effects are: first injection vs. subsequent injections, overall health, liver health, new alcohol use, and opioid clearance status. If opioids are still in the patient’s body, naltrexone can trigger a sudden withdrawal, which is why screening and timing are essential [3] to consider when starting treatment with naltrexone.
Clinical providers monitor the patient during the month after the first injection of naltrexone. Clinical staff will closely monitor the patient’s vital signs, any change in mood or emotion, how the injection site is healing, various aspects of well-being, as well as any new symptoms (i.e. breathing difficulty, jaundice, etc.) that could indicate stress on the liver [4]or adverse reactions. If any concerns arise, the clinical provider will respond promptly.
Common Vivitrol Side Effects
The majority of naltrexone patients will experience mild to moderate side effects that improve within a few days.
Common Symptoms Reported By Vivitrol Patients
Patients who are treated with naltrexone report the following side effects [2]:
- Nausea
- Headaches
- Dizziness/light-headedness
- Daytime sleepiness/fatigue
- Vomiting
- Reduced appetite
- Joint pain/muscle cramps
- Difficulty sleeping
- Toothaches
Most of the symptoms mentioned above occur soon after receiving the first injection and improve over time. Daytime sleepiness is a common early reaction, similar to how other medications affect alertness, which is why many people ask whether muscle relaxers make you sleepy.
Symptoms That Are Commonly Improved with Time
While nausea, headaches, and fatigue can persist for longer, they typically resolve within a few days to a couple of weeks after the first injection of naltrexone [5]. If the nausea, headache, or fatigue persists beyond this time frame and is affecting your daily activities, reach out to your prescribing provider. Your provider will work with you to identify if these symptoms are expected as you continue your treatment with naltrexone, to determine how to monitor the symptoms, and whether changes need to be made to your treatment plan.
For mild naltrexone-related symptoms (nausea, fatigue, headaches), patients can use self-care: stay hydrated, eat small, healthy meals, and get enough rest.
Serious Side Effects of Vivitrol
While less common, some side effects of naltrexone have the potential to become serious and may require immediate medical attention.
Severe Injection Site Reactions
Mild discomfort at the injection site is common; rarely, severe injection site reactions occur [4]. Severe injection site reactions can include severe pain, extreme swelling, infection, skin breakdown, or tissue necrosis, requiring medical evaluation.
Liver Damage & Hepatitis Warning
Naltrexone can affect the liver, particularly at higher doses or in people with pre-existing liver disease [6]. Symptoms that may signal liver problems include yellowing of the skin or eyes, dark urine, light-colored stools, persistent abdominal pain, or ongoing nausea. Any of these symptoms should be reported to a healthcare provider immediately.
Sudden Opioid Withdrawal Risk
If opioids were used recently, naltrexone can cause sudden and intense withdrawal symptoms [3]. This is why individuals must be opioid-free for a period of time before starting treatment unless medically managed in a supervised setting.
Recognizing recent opioid use matters before that first injection, and physical signs like dilated pupils from drugs can help indicate whether it is safe to begin treatment.
Risk of Opioid Overdose
Naltrexone blocks opioid effects, but trying to override that blockade by using large amounts of opioids can lead to overdose [5]. Additionally, after naltrexone wears off, opioid tolerance may be lower, increasing overdose risk if relapse occurs. This is a critical safety consideration discussed in treatment planning.
Serious Allergic Reactions
Rare but severe allergic reactions may include rash, facial or throat swelling, trouble breathing, chest pain, severe dizziness, or fainting [2]. These symptoms require emergency care.
Mood Changes and Depression
Some individuals report mood changes, including depression or suicidal ideation while taking naltrexone[4]. Any new or worsening mood symptoms should be taken seriously and discussed with a healthcare professional as soon as possible.
Injection Site Reactions – What You Should Know
What You Should Expect After An Injection
It is common to experience mild discomfort, tenderness, reddish color, and mild swelling at the injection site. These symptoms improve within a few days [5].
What You Should Report
Contact your provider if you notice increasing pain. Signs of an infection at the injection site that should be reported to the prescriber include spreading redness or warmth, drainage, fever, hardness that worsens over time, discoloration, an open area of skin, or any symptoms lasting more than approximately 2 weeks.
Differences Between Monthly Injections
Some individuals may have different reactions with subsequent naltrexone injections; some people may see a lessening of symptoms with each injection, while others may experience new side effects. Continual discussions with your treatment providers will usually enable you to continue taking naltrexone safely.
Risk Factors for Increased Side Effects
Alcohol Usage While Undergoing Treatment
Naltrexone is used for alcohol use disorder and opioid use disorder. People in recovery are advised to abstain from alcohol. Alcohol use while using naltrexone places an additional strain on the liver and may also lead to other overlapping side effects; as a result, your clinician will generally ask about your use of alcohol, as this will lessen your overall risk. The use of naltrexone for the treatment of alcohol use disorder will lessen the euphoria in response to alcohol. Trying to override the blunting of alcohol’s effects with more alcohol can lead to alcohol poisoning. Also, when no longer using naltrexone, the body will be less tolerant to alcohol, increasing the risk for alcohol overdose.
Having a History of Liver Disease or Certain Medications
If you have a history of liver disease or have taken prescription medications that have a documented interaction with naltrexone, there is an increased likelihood of experiencing side effects; therefore, a comprehensive medical assessment is necessary before prescribing naltrexone to minimize potential complications.
Because naltrexone can interact with other substances, it helps to review all your prescriptions, and understanding low-dose naltrexone drug interactions shows why a full medication list matters before your appointment.
Recent Opioid Use History
If you have been using opioids recently, you may be at risk for experiencing increased symptoms of withdrawal or may already be in withdrawal from your last use. Therefore, being appropriately screened and receiving the injection at the appropriate time is vital to ensuring the best start to your treatment with naltrexone.
Be Prepared for Your Appointment: You should take with you a complete list of medications and supplements you are taking; be prepared to have an honest discussion about any alcohol you use, and the date of your most recent use of opioids.
What To Do If You Experience Side Effects
How to Manage Mild Effects at Home
In many cases, mild nausea, headaches, or soreness can be managed by resting, drinking fluids, and monitoring symptoms. An ice pack for a sore injection site is helpful. You must contact your healthcare provider if your symptoms worsen or do not improve.
When to Contact Your Healthcare Provider
If you experience any of the following symptoms, you should contact your healthcare provider immediately: persistent vomiting, severe headaches, worsening injection-site symptoms or mood changes, especially thoughts of suicide.
When to Seek Emergency Medical Attention
If you experience any of the following severe or frightening symptoms, you should immediately seek emergency medical care: allergic reactions, difficulty breathing, chest pain, heart palpitations, fainting, or any other symptom that seems extreme.
Frequently Asked Questions About Vivitrol Side Effects
What are the most commonly experienced side effects of Vivitrol?
Nausea, headache, dizziness, fatigue, difficulty sleeping, and soreness in the injection area are the most commonly reported side effects associated with naltrexone [1]. The majority of individuals report that these mild side effects improve with time as their bodies adjust to the effects of naltrexone.
What are the serious side effects associated with Vivitrol?
Serious side effects associated with naltrexone include an increase in severity of injection-site reactions, liver problems, sudden onset of opioid withdrawal symptoms, allergic reactions, extreme mood changes, and increased overdose risks [2]. Serious side effects, while not common, should be treated as medical emergencies.
How long will I experience side effects after starting Vivitrol?
Most common side effects should resolve within several days and no longer than 2 weeks following your first injection [3]. However, because of the way naltrexone works in the body, some people continue to experience side effects for extended periods. Any ongoing or worsening side effects should be discussed with a healthcare provider.
What does a severe injection site reaction look like?
Symptoms that may indicate a severe injection site reaction may include increasing pain, spreading redness or warmth, drainage from the injection site, skin discoloration, and/or an opening in the injection area [4]. If you see any of these symptoms, you should contact a healthcare provider as soon as possible.
Is it possible for Vivitrol to cause liver problems, and what should I look for?
Yes, in some individuals, naltrexone may cause damage to the liver [6]. Warning signs of possible liver damage include yellowing of the skin and/or eyes, dark colored urine, light-colored stools, persistent abdominal pain, persistent nausea, and any combination of these warning signs. Individuals should report any of these symptoms to their healthcare provider immediately.
Is it possible for Vivitrol to induce withdrawal?
If you still have opioids in your body when starting naltrexone, there is a risk that you may experience withdrawal symptoms [5]. Therefore, before beginning naltrexone treatment, you must be opioid-free for a sufficient amount of time unless undergoing a medically supervised detoxification.
Is it safe to consume alcohol while taking Vivitrol?
Some people continue to consume alcohol while taking naltrexone; however, the possibility of increased side effects and increased risk of liver damage exists from alcohol consumption during naltrexone usage [6]. You must discuss your alcohol use with your healthcare provider so that an individualized treatment plan can be developed safely.
Will Vivitrol impact my mood or mental health?
Mood and mental health changes, such as depression and suicidal thoughts, have been reported by some individuals [4]. Should an individual experience new or worsening mood/mental health symptoms, it is essential to talk to a healthcare provider as soon as possible.
How New Wave Recovery Center Helps Clients Using Medication-Assisted Treatment
At New Wave Recovery Center, we provide an individualized, comprehensive approach for each client. Clients who attend outpatient, half-day treatment, and day treatment receive counseling and evidence-based (research-validated) therapies like cognitive behavioral therapy (CBT), which focuses on identifying and changing unhelpful thoughts and behaviors, and dialectical behavior therapy (DBT), which helps people manage intense emotions and behaviors. These are combined with holistic recovery services.
The process of determining which medications work best for clients is conducted on an individual basis in conjunction with the prescribing clinician. Our goal is to provide clients with educational opportunities, ongoing monitoring, and open communication so they feel supported and informed throughout their treatment.
If you would like additional information about naltrexone or have concerns about side effects, our staff is available to help you explore your treatment options and understand what to expect. Working with qualified professionals can provide you with valuable information and support during your recovery journey.
Also medication works best alongside connection with others, and joining support groups in Massachusetts gives you an added layer of encouragement throughout your recovery.
Sources:
[1] Ghai, R., & Gupta, V. (2024). Naltrexone. StatPearls. National Center for Biotechnology Information. https://www.ncbi.nlm.nih.gov/books/NBK534811/
[2] U.S. Food and Drug Administration. (2022). VIVITROL (naltrexone for extended-release injectable suspension) Prescribing Information. https://www.accessdata.fda.gov/drugsatfda_docs/label/2022/021897s057lbl.pdf
[3] Lee, J. D., Nunes, E. V., Jr, Novo, P., et al. (2018). Comparative effectiveness of extended-release naltrexone versus buprenorphine-naloxone for opioid relapse prevention (X:BOT). The Lancet. https://pmc.ncbi.nlm.nih.gov/articles/PMC5806119/
[4] Substance Abuse and Mental Health Services Administration. (2024). Clinical Use of Extended-Release Injectable Naltrexone in the Treatment of Opioid Use Disorder. https://library.samhsa.gov/sites/default/files/sma14-4892r.pdf
[5] Jarvis, B. P., et al. (2018). Extended-release injectable naltrexone for opioid use disorder: A systematic review. Addiction. https://pmc.ncbi.nlm.nih.gov/articles/PMC5993595/
[6] National Institute of Diabetes and Digestive and Kidney Diseases. (2020). Naltrexone. LiverTox: Clinical and Research Information on Drug-Induced Liver Injury. https://www.ncbi.nlm.nih.gov/books/NBK548583/
