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How Long Does Naltrexone Take to Work? Naltrexone tablets start working within 1 to 2 hours of the first dose, but a noticeable reduction in alcohol cravings usually takes 2 to 3 days of consistent use. The duration of Naltrexone injections (Vivitrol) varies. Understanding the Naltrexone timeline can help you set realistic expectations and maximize its benefits.
ChoicePoint offers online Naltrexone prescriptions and monthly Naltrexone injection plans to curb alcohol and opioid cravings. Call 844.445.2565 to schedule an appointment online.
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What is Naltrexone?
Naltrexone is an FDA-approved prescription medication used to reduce cravings and block the pleasurable effects of alcohol and opioids. It is not addictive, does not cause withdrawal, and is commonly used as part of medication-assisted treatment.1
How Naltrexone Works to Block the Effects of Alcohol and Opioids?
How does Naltrexone work? Well, Naltrexone, used for alcohol and opioid treatment, works by attaching to the same receptors in the brain that alcohol and opioids normally activate. These receptors are responsible for producing pleasure, euphoria, and reinforcement. When Naltrexone is present, it acts as a blocker. This prevents alcohol or opioids from creating the usual “reward” effect. 2
Forms of Naltrexone
- Oral tablet: Naltrexone 100 mg and Naltrexone 50 mg. Taken once daily
- Extended-release injection: Given once a month (also known as Vivitrol)
How Long Does Naltrexone Take to Work?
Naltrexone begins to take effect soon after the first dose. Most individuals feel some effect within a few hours. However, a noticeable reduction in craving and full therapeutic benefit may take a few days of consistent use.
Oral Naltrexone (Tablet)
- Begins working within 1 to 2 hours
- Reaches its full effect in 2 to 3 days of consistent use
Vivitrol (Monthly Injection)
- Used for opioid and alcohol dependence treatment
- Begins working within 2 hours after the injection
- Provides steady effects for about 28 to 30 days
How Long Does Naltrexone Block Opiates?
Naltrexone blocks the effects of opioids for about 24 hours when taken as a daily oral tablet, while the extended-release injection blocks opioids continuously for approximately 28 to 30 days. The exact duration depends on the dose and formulation, but both forms prevent opioids from producing euphoria or pain relief during the blocking period.
Why Patients Choose ChoicePoint for Naltrexone Treatment
How Fast Does Naltrexone Start Reducing Alcohol Cravings?
Naltrexone begins reducing alcohol cravings quickly. Most individuals feel the first signs of craving relief within 24 to 48 hours of starting the medication. Some notice changes even sooner because the oral tablet begins working within 1 to 2 hours.3
How Long Does It Take for Naltrexone to Reach Full Effect?
Naltrexone reaches its full effect within a few days of consistent use. For most individuals, steady therapeutic levels build within 2 to 3 days, allowing the medication to fully block alcohol’s rewarding effects and provide reliable craving control. 4
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How Long Does It Take For Naltrexone Effects To Wear Off?Naltrexone effects wear off in about 24 to 72 hours after the last oral dose, depending on the dose and how quickly the body metabolizes the medication. For the extended-release injection, the effects gradually fade over approximately 28 to 30 days.
Naltrexone Timeline: What to Expect During the First Week?
Starting Naltrexone for the first time? Here are a few things to expect:
| Timeline Stage | Oral Naltrexone Tablet | Naltrexone Injection (Vivitrol) |
|---|---|---|
| Day 1 | Starts working in 1 to 2 hours. Mild craving reduction may begin the same day. | Begins working within 2 hours of the injection. Early craving relief is possible the same day. |
| Days 2–3 | Medication reaches steady levels. Noticeable craving reduction for many individuals. | The injection stabilizes quickly. Most people feel strong craving control by day 2. |
| Days 4–5 | Alcohol becomes less rewarding. Urges feel easier to manage during typical trigger times. | Effects remain steady. Alcohol’s pleasurable effects stay consistently blocked. |
| Days 6–7 | Full therapeutic effect is usually felt. Cravings are significantly lower by the end of the week. | Full effect typically occurs within 48 hours and remains stable throughout the week. |
| Overall Effect | Builds gradually over several days. Works best with consistent daily dosing. | Fast onset with continuous coverage for 28–30 days. |
Important Considerations When Taking Naltrexone
To gain maximum benefits out of your naltrexone treatment, it is essential to:
- Share your full medical history with the doctor, especially if you have any liver or kidney issues.
- Avoid using any opioids.
- Certain medications may interact with Naltrexone, so it is important to inform your healthcare provider.
- Regular health monitoring and liver checks are important when taking this medication.
- Be aware of side effects such as:
- Nausea
- Headaches
- Fatigue
- Joint or muscle pain
- Take the exact dosage at the exact schedules recommended by your doctors
- If you miss a dose, take the medicine as soon as possible. If it is almost time for your next dose, take it. Do not double the dose.
- Stop using opioids for at least 7-10 days before you can start taking Naltrexone.
What User Usually Experiences?
Here are some user experiences to help you understand what you may go through:
Starting Naltrexone at ChoicePoint was a turning point for me. The cravings felt quieter, and I could finally focus on therapy without constantly battling urges. The support team checked in often, which made the process feel safe. Get your online Naltrexone prescription today by calling 844.445.2565.
Scheduling an Appointment With Online Naltrexone Doctors in NJ at ChoicePoint
Naltrexone doctors are addiction specialists licensed to dispense Naltrexone oral prescriptions and administer monthly Naltrexone injections at Vivitrol clinics. Our online Naltrexone doctors are also available for online consultations to evaluate the medical need and adjust the Naltrexone dosage, thereby devising a suitable treatment plan.
Choose the ChoicePoint Vivitrol and Naltrexone Clinic For
Choose ChoicePoint for:
- Extra Convenience: Speak to addiction counselors, therapists, and doctors from the comfort of your home.
- Added Privacy: All our treatments are HIPAA-compliant
- Excellent Insurance Coverage: Both online prescriptions and monthly Vivitrol injections are covered by BCBS and other major insurance companies such as Aetna, UnitedHealth, and Optum, NJ.
Verify your insurance online to check if we accept your insurance plan.
Scheduling an Appointment to get an online Naltrexone prescription in NJ
Here is how to get an online Naltrexone prescription today
- Schedule an appointment online
- Request a call back
- Call 844.445.2565 to speak to a representative
Get started today to enjoy a substance-free life!
FAQs Related to Naltrexone Onset of Action
More of your questions are answered below:
1. Is Naltrexone Addictive?
No, naltrexone is not addictive. Both injectable and oral forms do not cause any dependence.
2. Can I Drink Alcohol While on Naltrexone?
Naltrexone blocks the euphoric effects of alcohol, and there may not be any serious dangers of alcohol and naltrexone. But, drinking on Nalrexone is highly discouraged as it defeats the purpose of treatment. And, you may still experience alcohol withdrawal and hangover, jeopardizing your recovery.
3. How Long Does Naltrexone Take to Work For Pain?
Naltrexone does not work as a traditional pain reliever. At standard doses, it blocks opioid pain medications and does not provide pain relief. When used off-label as low-dose naltrexone for pain or inflammation, some people begin to notice benefits within 1 to 4 weeks.
4. How Long Does Naltrexone Stay in the System?
Naltrexone stays in the body for several days after the last dose. Oral naltrexone is typically cleared within about 2 to 3 days
References
- Medications for Opioid Use Disorder: For Healthcare and Addiction Professionals, Policymakers, Patients, and Families: Updated 2021 [Internet]. Rockville (MD): Substance Abuse and Mental Health Services Administration (US); 2018. (Treatment Improvement Protocol (TIP) Series, No. 63.) Chapter 3C: Naltrexone. Available from: https://www.ncbi.nlm.nih.gov/books/NBK574913/
- Singh D, Saadabadi A. Naltrexone. [Updated 2023 May 30]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK534811/
- https://go.drugbank.com/drugs/DB00704
- Center for Substance Abuse Treatment. Incorporating Alcohol Pharmacotherapies Into Medical Practice. Rockville (MD): Substance Abuse and Mental Health Services Administration (US); 2009. (Treatment Improvement Protocol (TIP) Series, No. 49.) Chapter 5—Extended-Release Injectable Naltrexone. Available from: https://www.ncbi.nlm.nih.gov/books/NBK64031/
Medical Disclaimer:
ChoicePoint aims to improve the quality of life for people struggling with substance use disorder and mental health issues. Our team of licensed medical professionals research, edit and review the content before publishing. However, this information is not intended to be a substitute for professional medical advice, diagnosis, or treatment. For medical advice please consult your physicians or ChoicePoint's qualified staff.
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Professional Support. Proven Medication.
