Naltrexone Implant vs Oral Naltrexone vs Vivitrol: Duration, Adherence, Cost and Evidence
Oral naltrexone, monthly extended-release injectable naltrexone and sustained-release naltrexone implants all use the opioid antagonist naltrexone, but they should not be treated as interchangeable treatments. They differ in dosing frequency, adherence demands, evidence, procedure requirements, regulatory status and how treatment costs are structured.
DeBinge opioid transition: When travelling to DeBinge in The Bahamas for OLANI treatment, there is no requirement to complete a separate opioid-free waiting window before arrival. DeBinge uses a medically supervised 4-to-5-day buprenorphine transition. Buprenorphine is introduced to bridge the patient away from full-agonist opioids, stabilised and tapered over the first several days, and the O’Neil Long-Acting Naltrexone Implant is typically inserted around day 4 or 5 while buprenorphine is still being tapered. The planned overlap continues as buprenorphine clears and the implant gradually releases naltrexone. This pathway is clinician-supervised because mistimed naltrexone exposure can precipitate withdrawal.
Based on DeBinge’s clinical experience in The Bahamas since 2018, the implant typically provides its strongest craving and relapse-prevention support on average 9 months, while clinically meaningful opioid-receptor blockade may persist for longer, in some patients up to about 15 months. This longer blockade may continue to reduce opioid effects and overdose risk.
Ongoing recovery: The implant is not a cure. The DeBinge programme includes a full year of professional counselling after implantation to address the behavioural and psychological side of addiction.
For opioid use disorder, the central question is not simply which formulation provides the longest blockade. A treatment must first be safe to start, clinically appropriate, realistically sustainable and connected to counselling, overdose planning and longer-term recovery support.
Oral naltrexone formulations and extended-release injectable naltrexone are available within established U.S. regulatory pathways. Naltrexone implant formulations are not FDA-approved for clinical use in the United States. DeBinge implant-based treatment takes place in Nassau, The Bahamas.
Which Form of Naltrexone Is Most Effective?
There is no responsible evidence-based answer that identifies one formulation as universally best.
Oral naltrexone avoids an injection or implantation procedure and allows treatment to be changed relatively easily, but its effect depends heavily on continued medication adherence.
Extended-release injectable naltrexone, commonly known as Vivitrol®, reduces daily adherence demands by providing approximately one month of medication exposure after each injection. It has standardized FDA-approved U.S. labeling and a substantially stronger regulatory and clinical evidence base than implant formulations.
Sustained-release implants can extend medication exposure further and may reduce repeated adherence decisions, but implant products differ and evidence from one formulation should not automatically be applied to another.
The 2025 Cochrane review of sustained-release naltrexone concluded that sustained-release treatment may reduce illicit opioid use compared with oral naltrexone, but certainty was limited for several other outcomes. The same review did not establish sustained-release naltrexone as superior to opioid agonist treatment such as buprenorphine or methadone.
For background on the pharmacology and safety of implants, see the long-acting naltrexone implant guide.
How Does Naltrexone Work?
Naltrexone is an opioid receptor antagonist. It binds strongly to opioid receptors, particularly mu-opioid receptors, without activating them. While adequate antagonist concentrations are present, naltrexone can substantially reduce or block the effects of opioids such as heroin, fentanyl, oxycodone and morphine.
That mechanism is fundamentally different from methadone, a full opioid agonist, and buprenorphine, a partial opioid agonist. Naltrexone does not maintain opioid dependence and does not produce the same opioid agonist effects.
The trade-off is that naltrexone normally cannot be started safely while significant opioid physical dependence remains. Administering an antagonist too early can abruptly displace opioid activity and trigger severe precipitated withdrawal.
The medication molecule is the same across oral, injectable and implant approaches. What changes is how long clinically relevant drug exposure persists and how frequently the patient must actively choose to continue treatment.
Oral Naltrexone vs Vivitrol vs Naltrexone Implant
| Feature | Oral Naltrexone | Vivitrol / Extended-Release Injection | Sustained-Release Implant |
|---|---|---|---|
| Medication | Naltrexone | Naltrexone | Naltrexone |
| Administration | Tablet taken according to the prescribed schedule | Deep intramuscular gluteal injection by a healthcare professional | Subcutaneous implantation procedure |
| Dosing frequency | Usually daily in routine treatment | 380 mg every four weeks or approximately once monthly | Product-specific; studied formulations may release medication for multiple months |
| Adherence issue | Requires repeated patient participation | Requires returning for repeat injections | Reduces repeated dosing decisions during the active release period |
| FDA-approved U.S. implant? | Not an implant; oral formulations are available in the U.S. | Yes, Vivitrol is FDA-approved for specified indications | No |
| Procedure-specific risk | No injection or implantation procedure | Injection-site reactions, including rare severe reactions | Implant-site pain, infection, wound complications and other product/procedure-specific risks |
| Stopping treatment | Medication exposure declines after tablets are discontinued | The administered depot cannot simply be withdrawn after injection | Management or removability depends on the exact implant product |
Oral Naltrexone: Flexible but Adherence-Dependent
Oral naltrexone is the oldest of the three approaches. Current U.S. prescribing information for naltrexone tablets includes treatment of alcohol dependence and blockade of the effects of exogenously administered opioids as part of an appropriate addiction-management plan.
For opioid dependence, current product labeling describes a 50 mg daily maintenance dose after safe initiation. Individual prescribing decisions belong to the treating clinician.
Legitimate strengths
- no injection or implantation procedure;
- comparatively easy to discontinue or change under medical supervision;
- generic formulations can make the medication itself relatively inexpensive compared with proprietary long-acting medication;
- provides effective opioid receptor antagonism when taken consistently.
The major limitation: taking it consistently
Oral naltrexone has long been limited by adherence in opioid use disorder. The medication can only provide blockade while the patient continues taking it. Missing doses, stopping medication intentionally before planned opioid use or gradually disengaging from treatment can remove the intended protection.
Current oral naltrexone labeling explicitly notes that the medicine has demonstrated value when compliance is supported as part of a comprehensive treatment plan.
That adherence limitation is one reason monthly injections and implants were developed.
Vivitrol: Approximately One Month of Naltrexone per Injection
Vivitrol is a microsphere formulation containing 380 mg of naltrexone. Current FDA prescribing information specifies a deep intramuscular gluteal injection every four weeks or once a month, administered by a healthcare professional.
In the United States, Vivitrol is FDA-approved for alcohol dependence in appropriately selected patients and for prevention of relapse to opioid dependence following opioid detoxification. FDA labeling states that treatment should form part of a comprehensive management program including psychosocial support.
Legitimate strengths
- standardized FDA-approved U.S. product and prescribing information;
- approximately monthly rather than daily adherence;
- established clinical-trial evidence;
- no surgical implantation procedure;
- regular monthly contact can create recurring opportunities for clinical review.
Limitations
- the patient must return for repeated injections;
- a missed or delayed injection can create a gap in continuing antagonist treatment;
- injection-site reactions can occur and rare severe reactions have required surgical management;
- the patient still has to complete appropriate opioid-free preparation before treatment for OUD;
- cost and insurance arrangements vary substantially.
Sustained-Release Naltrexone Implants: Longer Exposure, More Product-Specific Questions
A naltrexone implant places a sustained-release formulation beneath the skin so that naltrexone is released gradually rather than requiring daily tablets or monthly injections.
The potential adherence advantage is straightforward. Once a suitable long-acting formulation has been placed, the patient does not need to remember a tablet every day or return every four weeks for another injection during the implant’s active release period.
But the term “naltrexone implant” is not one standardized medicine. Different studies have investigated different doses, polymer systems, release profiles and intended treatment durations.
This is why statements such as “the implant lasts a year” or “implants work better than tablets” require product-specific evidence.
FDA approval of oral naltrexone or Vivitrol does not transfer to a subcutaneous implant simply because the active ingredient is also naltrexone.
Implant treatment also introduces a procedure site. Published trials have reported wound and implant-site complications, so procedural risk needs to be evaluated separately from the pharmacology of naltrexone.
Does Longer Duration Improve Opioid-Relapse Outcomes?
Longer exposure can address an important weakness of oral antagonist treatment: the patient cannot receive pharmacological benefit from a dose that is not taken.
That makes adherence a plausible reason why a sustained-release formulation may outperform unsupervised oral naltrexone in some situations.
It does not mean longer duration automatically produces better overall recovery.
Clinical outcomes depend on more than drug concentration. They can be affected by whether treatment was successfully initiated, counselling, psychiatric health, social environment, other substance use, treatment retention and what happens after medication coverage declines.
An implant can reduce medication decisions. It cannot ensure attendance at counselling, repair relationships, change high-risk environments or guarantee that a patient will not attempt substance use.
The Australian Implant-vs-Oral Naltrexone Trial: What It Actually Found
Hulse and colleagues, 2009
This randomized, double-blind, double-placebo trial was conducted in Perth, Western Australia.
The study included 70 adults with heroin dependence who had completed screening and agreed to randomization.
Thirty-five participants received daily oral naltrexone at 50 mg plus placebo implants. Thirty-five received a single 2.3 g sustained-release naltrexone implant plus placebo tablets. Follow-up lasted six months.
Participants in the implant group maintained therapeutic naltrexone concentrations more consistently during the early months of treatment. More patients assigned to oral naltrexone had returned to regular heroin use by six months, and return to regular heroin use occurred earlier in the oral group. Median time to regular heroin use was reported as approximately 115 days in the oral group compared with 158 days in the implant group.
This trial provides evidence that a sustained-release implant can overcome some of the adherence limitations of daily oral naltrexone in a particular population.
What the trial does not prove
It does not prove that every modern implant is superior to oral naltrexone. It studied one 2.3 g formulation, 70 participants, heroin dependence, one Australian metropolitan population and a treatment context from more than 15 years ago.
The opioid supply has also changed substantially since then. Contemporary U.S. treatment increasingly involves fentanyl and polysubstance exposure, populations that were not represented in this Australian trial.
The findings also cannot be used as a direct implant-versus-Vivitrol comparison because Vivitrol was not the comparator.
What Other Randomized Implant Research Shows
A separate 2012 randomized trial conducted in addiction-treatment programs in St Petersburg, Russia enrolled 306 recently detoxified opioid-dependent patients.
Participants received biweekly counselling and were randomized to a 1,000 mg naltrexone implant plus oral placebo, placebo implant plus 50 mg daily oral naltrexone or double placebo.
At six months, 52.9% of participants assigned to the implant remained in treatment without relapse, compared with 15.7% in the oral-naltrexone group and 10.8% in the placebo group.
This was an important controlled study supporting the ability of that sustained-release formulation to improve treatment retention without relapse relative to oral naltrexone in that setting.
Again, it was not a Vivitrol comparison and not evidence that all implant products produce the same result.
What Does the 2025 Cochrane Review Say?
The 2025 Cochrane review is especially useful because it evaluates sustained-release naltrexone as a broader evidence category rather than relying on a single trial.
The review included 22 randomized studies involving 3,416 participants. Studies compared injectable or implantable sustained-release naltrexone with opioid agonist treatment, oral naltrexone, placebo, treatment as usual or psychosocial treatment.
Compared with oral naltrexone
Low-certainty evidence suggested sustained-release naltrexone may reduce in-treatment illicit opioid use. Evidence concerning retention and serious adverse events was much less certain.
Compared with treatment as usual
High-certainty evidence indicated reduced in-treatment illicit opioid use, although retention effects were limited or uncertain.
Compared with opioid agonist treatment
Sustained-release naltrexone did not demonstrate superiority. Moderate-certainty evidence suggested slightly more in-treatment illicit opioid use in one comparison, while retention and acceptability remained uncertain.
Main evidence gaps
The reviewers highlighted small studies, inconsistent formulations, limited long-term follow-up and insufficient evidence in people using contemporary synthetic opioids.
The practical interpretation is not that long-acting naltrexone “wins” or “loses.” Sustained delivery may improve some outcomes where adherence is the major problem, but formulation choice still needs individual clinical context.
New Longer-Duration Implants Are Still Being Studied
Implant technology continues to evolve.
A 2026 first-in-human Phase I study evaluated a newer bioresorbable implant known as iSTEP-N, designed with the goal of releasing naltrexone for six to twelve months.
The study included only 16 healthy adults and primarily examined pharmacokinetics and safety. The higher-dose group maintained mean plasma concentrations above the prespecified opioid-blockade threshold during the 12-week study period, while less than one-quarter of the implanted drug content had been released by 12 weeks.
That is promising early pharmacokinetic research. It is not evidence that this experimental product prevents relapse for 6–12 months or that it is clinically superior to oral naltrexone or Vivitrol.
All Three Forms Require Attention to Opioid-Free Preparation
Naltrexone is an antagonist regardless of whether it comes as a tablet, injection or implant. A longer-lasting delivery system does not remove the need for safe induction.
Current U.S. labeling for oral naltrexone and Vivitrol recommends an opioid-free interval before initiation. For people previously dependent on short-acting opioids, current labeling commonly references at least 7–10 days. People transitioning from buprenorphine or methadone may remain vulnerable to precipitated withdrawal for as long as approximately two weeks.
These numbers should not be used as a universal self-detoxification timetable. Fentanyl exposure, repeated opioid use, long-acting medications, individual physiology and uncertain street-drug composition can complicate preparation.
An opioid-dependent patient who receives naltrexone too early can experience abrupt precipitated withdrawal severe enough to require hospital-level care.
Read more about opioid use disorder treatment and long-acting naltrexone.
What Does Opioid Blockade Actually Mean?
When sufficient naltrexone is present, subsequently used opioids may produce substantially reduced euphoric, sedating and analgesic effects.
That can support treatment, but opioid receptor blockade should not be described as an impenetrable barrier or guaranteed overdose prevention.
Trying to overcome the blockade
FDA prescribing information for extended-release injectable naltrexone warns that its competitive opioid blockade is surmountable. Taking very large opioid doses in an attempt to overpower the blockade can cause life-threatening or fatal opioid poisoning.
Reduced opioid tolerance
Tolerance typically declines during abstinence. When naltrexone coverage fades or treatment is discontinued, a dose that was previously tolerated may become dangerous.
Naloxone still matters
Patients with opioid-overdose risk and their families should discuss access to naloxone or another locally available overdose-reversal medication with a clinician. Naltrexone is not an emergency overdose-reversal medicine.
Pain treatment matters too
Long-acting antagonist treatment can complicate opioid analgesia. Anyone expecting surgery, dental treatment or another situation where opioid analgesics might be required should discuss this before choosing a long-duration formulation.
What Happens When Naltrexone Treatment Ends?
The end of medication coverage is clinically important regardless of formulation.
With oral naltrexone, stopping tablets removes the recurring medication exposure relatively quickly. With Vivitrol, exposure gradually declines after the injection. With an implant, the timeline depends on the particular formulation and its release characteristics.
None of these situations means that previous opioid tolerance returns automatically.
A patient who has spent weeks or months abstinent from opioids may have markedly reduced tolerance. Resuming a dose that was previously familiar can therefore cause overdose.
This is why the recovery plan should include what happens after long-acting treatment, not simply what happens while blockade is present.
Longer Medication Coverage Does Not Replace Recovery Treatment
Medication changes pharmacology. Counselling addresses different parts of addiction.
That can include triggers, emotional regulation, stress, relationships, trauma, work problems, boredom, routines, social networks and planning for high-risk situations.
SAMHSA describes naltrexone as one component of a comprehensive treatment plan, and current Vivitrol labeling explicitly states that treatment should include psychosocial support.
One useful way to think about a long-acting formulation is that it may create a period during which fewer medication-adherence decisions are required. The clinical value of that time depends partly on what is done with it.
Why Naltrexone Cost Comparisons Are Often Misleading
Searching for “long-acting naltrexone cost” can produce numbers that appear easy to compare but actually represent completely different things.
A pharmacy acquisition price is not the same as a patient’s insurance cost. A single monthly injection is not the same as a year’s medication. And the cost of one medication dose is not comparable with an international treatment package that includes clinical services, accommodation and continuing counselling.
| Cost Type | What It Means |
|---|---|
| Medication retail/acquisition price | The gross price or acquisition benchmark for the medication itself. |
| Insurance allowable amount | The amount recognized under a particular health-plan arrangement. |
| Patient out-of-pocket cost | What remains after insurance, deductible, coinsurance, copayment or eligible assistance. |
| Program price | A bundled charge that may include medical treatment, accommodation, counselling and other services. |
What Does Oral Naltrexone Cost?
Generic oral naltrexone is generally the simplest formulation to price because there is no injection administration or implantation procedure. However, actual U.S. patient cost still depends on pharmacy pricing, insurance, deductible and the prescribed treatment plan.
A medication that is inexpensive per tablet may still provide poor value if the patient repeatedly stops taking it. Conversely, someone who is highly adherent may not need a more complex long-acting delivery system merely because one exists.
Cost therefore needs to be evaluated together with realistic adherence.
How Does U.S. Insurance Affect Vivitrol Cost?
Because Vivitrol is an FDA-approved prescription medication, U.S. patients may be able to use health insurance toward treatment when their individual plan provides coverage.
Coverage is not universal and the amount paid by the patient cannot be inferred from the list or acquisition price. Insurance plans may have different network requirements, deductibles, coinsurance rules, prior authorization processes and billing pathways.
The only reliable way to know an individual’s insurance cost is to verify benefits with that patient’s plan and treatment provider.
Current manufacturer co-pay assistance
As of September 2026, the Vivitrol manufacturer states that eligible commercially insured or cash-paying U.S. patients may qualify for its co-pay savings program. Current terms provide up to $500 per prescription for up to 12 prescriptions per calendar year, with a maximum benefit of $6,000 annually.
The program does not cover associated office visits or medication-administration charges, and patients using Medicare, Medicaid or other specified government healthcare programs are not eligible for this commercial co-pay program.
This is a manufacturer assistance program, not a guarantee of insurance coverage or a guarantee that a patient will pay $0.
What Does the DeBinge Long-Acting Naltrexone Program Cost?
The exact price depends on individual treatment requirements.
Current DeBinge treatment information lists approximately $21,000–$23,000 for the broader treatment program rather than for the implant product alone.
Current DeBinge program information describes the package as including, according to the individual’s clinical plan:
- individual medical assessment and clinical care;
- appropriate preparation before long-acting naltrexone when clinically required;
- long-acting naltrexone treatment for clinically suitable patients;
- private medical and nursing support during the clinical treatment stage;
- accommodation associated with the Nassau treatment period;
- one full year of professional counselling;
- continuing recovery support after the clinical stage.
The exact treatment plan and what is required for a particular patient should be confirmed during assessment and in the patient’s current written program information before payment.
Comparing approximately $21,000–$23,000 for a broader international treatment program with the pharmacy cost of one monthly injection would make the implant program look artificially expensive. Comparing the package with twelve injections alone can also be misleading because U.S. insurance may substantially change patient cost while the services included in each pathway differ.
For information about where the procedure is performed, see naltrexone implant treatment availability in the United States and The Bahamas.
What Should a Real Cost Comparison Include?
Medication
How much does the drug itself cost, and for how long is clinically relevant exposure expected?
Administration
Are repeated clinic visits, injections, procedures or professional fees required?
Preparation
Is opioid withdrawal or other medical preparation required, and is that care included?
Counselling
Is behavioural treatment included, or will it need to be arranged and paid for separately?
Insurance
Which components are covered, subject to deductible or excluded from the individual’s health plan?
Travel and time
What travel, accommodation, time away from work or recurring appointment costs apply?
For this reason, “Which option costs less?” is usually less informative than “What will my complete treatment pathway cost, and what services does that pathway actually include?”
Naltrexone Is Not the Only Medication Strategy
A comparison of oral naltrexone, Vivitrol and implants should not create the impression that every patient with opioid use disorder needs to choose among these three antagonist formulations.
Methadone and buprenorphine are evidence-based medications for OUD with extensive clinical evidence. Their pharmacology and initiation process differ from naltrexone.
The 2025 Cochrane review did not establish sustained-release naltrexone as superior to opioid agonist treatment. For people who repeatedly cannot complete the opioid-free transition required for antagonist therapy, discussing buprenorphine or methadone may be particularly important.
Medication selection should reflect medical history, current opioid use, previous treatment, treatment goals, patient preference, ability to complete induction, overdose risk and access to continuing care.
Does This Comparison Change for Alcohol Use Disorder?
Yes. Naltrexone is an established treatment for alcohol use disorder, but the evidence differs by formulation.
Oral naltrexone has substantial AUD evidence, and extended-release injectable naltrexone is FDA-approved for alcohol dependence in appropriately selected patients.
Implant-specific evidence for AUD is much smaller and should not be treated as equivalent to the oral or Vivitrol evidence base.
For a focused review, see naltrexone implants and alcohol use disorder: what the evidence actually shows.
Questions to Ask About Any Long-Acting Naltrexone Program
- Which exact formulation is being proposed?
- What evidence specifically relates to that formulation?
- How long is clinically relevant naltrexone exposure expected to continue?
- What regulatory status applies in the country where treatment takes place?
- How will opioid-free readiness be assessed?
- What happens if I cannot complete antagonist induction?
- What procedure or administration risks apply?
- How are emergency pain-management needs handled?
- What counselling accompanies medication?
- What happens when medication coverage begins to decline?
- How will overdose risk and access to naloxone be addressed?
- Exactly what is included in the quoted treatment price?
See the full guide to questions for comparing naltrexone implant programs.
Which Naltrexone Questions Should You Take to Your Doctor?
This tool does not choose oral naltrexone, Vivitrol or an implant for you. It identifies questions that may deserve more attention during an individual medical consultation.
Your answers are processed only in your browser and are not submitted to DeBinge.
Questions to Take to Your Clinician
Your responses highlight areas that may need more discussion. They do not identify which formulation is appropriate.
Oral Naltrexone vs Vivitrol vs Implant FAQ
Is a naltrexone implant more effective than oral naltrexone?
Some randomized trials found better outcomes with particular sustained-release implants than with daily oral naltrexone, consistent with the theory that long-acting delivery can reduce adherence problems. However, these results relate to specific implant formulations and populations and cannot automatically be generalized to every implant.
Is a naltrexone implant more effective than Vivitrol?
Current evidence does not establish all implants as universally more effective than FDA-approved extended-release injectable naltrexone. Direct modern head-to-head implant-versus-Vivitrol evidence is limited.
How long does oral naltrexone work?
Oral naltrexone is generally prescribed on a recurring schedule, commonly daily. Continued blockade depends on continuing to take the medication as prescribed.
How long does Vivitrol work?
Vivitrol is administered every four weeks or approximately once per month under current FDA prescribing information.
How long does a naltrexone implant last?
There is no single duration for all implants. Published products and experimental formulations have different doses and release profiles. Duration should be supported by data relating to the exact product being offered.
Are naltrexone implants FDA-approved?
Naltrexone implant formulations are not FDA-approved for clinical use in the United States.
Does insurance cover Vivitrol?
Coverage and out-of-pocket cost vary by individual U.S. health plan. Patients should verify benefits, authorization requirements and administration costs directly with their insurer and treatment provider rather than assuming coverage.
Does insurance cover naltrexone implants in the U.S.?
Naltrexone implants do not have the same standard FDA-approved U.S. insurance pathway because implant formulations are not FDA-approved for clinical use in the United States. International program costs and possible reimbursement questions should be confirmed individually rather than assumed.
How much does the DeBinge treatment program cost?
Current DeBinge information lists an approximate program price of $21,000–$23,000 USD depending on individual treatment requirements. It is a broader treatment package rather than the price of an implant alone.
What is included in the DeBinge price?
Current DeBinge program information describes medical assessment and clinical care, appropriate preparation, long-acting naltrexone for suitable patients, private medical and nursing support during the clinical stage, accommodation associated with treatment in Nassau, one year of professional counselling and continuing recovery support. Exact patient-specific inclusions should be confirmed before treatment.
Do all naltrexone treatments require opioid detox first?
A person who is physically dependent on opioids must complete appropriate opioid-free preparation before naltrexone antagonist treatment. Starting naltrexone too early can cause severe precipitated withdrawal.
Can someone overdose after stopping naltrexone?
Yes. Opioid tolerance may be substantially reduced after abstinence. Returning to doses previously tolerated can therefore result in life-threatening overdose. Overdose education and naloxone planning remain important.
Do I still need counselling if I have a long-acting implant?
Yes. Long-acting medication can address adherence and opioid receptor blockade, but counselling addresses psychological, behavioural and social components of recovery that medication alone cannot resolve.
Evidence Used in This Comparison
FDA / DailyMed: Vivitrol
Current prescribing information covering FDA-approved indications, 380 mg monthly dosing, opioid-free initiation, precipitated withdrawal, overdose vulnerability, injection-site reactions and psychosocial support.
DailyMed: Oral Naltrexone
Current naltrexone hydrochloride tablet labeling covering alcohol dependence, opioid blockade, initiation requirements, adherence and overdose-reversal planning.
SAMHSA: Naltrexone
SAMHSA information describing naltrexone as part of comprehensive substance-use treatment and differentiating oral and extended-release injectable formulations.
Cochrane 2025
Kornør H, Lobmaier PPK, Kunøe N. Sustained-release naltrexone for opioid dependence. Cochrane Database of Systematic Reviews. 2025.
Hulse et al., Australia
Randomized trial of a 2.3 g sustained-release implant versus daily oral naltrexone in 70 adults with heroin dependence in Perth, Western Australia.
Krupitsky et al., Russia
Randomized six-month trial of a 1,000 mg naltrexone implant, oral naltrexone or placebo in 306 recently detoxified opioid-dependent patients.
2026 Phase I Implant Research
First-in-human pharmacokinetic study of a newer bioresorbable long-acting implant. Early-phase evidence should not be treated as proof of long-term clinical relapse prevention.
Vivitrol Co-Pay Program
Current manufacturer terms describing eligibility and assistance limits. Program terms can change and do not constitute a guarantee of insurance coverage.
Evidence, regulatory information and DeBinge program pricing were checked in September 2026. Medication labeling, assistance programs, prices and treatment packages may change. Patients should confirm current information before making treatment or financial decisions.
Prepared for Medical Review by Dr Fergus Law, BSc, MBChB, FRCPsych
Consultant Psychiatrist specialising in substance misuse and addiction psychiatry.
This comparison has been prepared as an evidence-based educational resource and is awaiting formal clinical approval. Until that process is complete, it should not be represented as having been medically reviewed.
View Dr Fergus Law’s professional profile
Review status: Pending clinical approvalThis Comparison Does Not Choose a Medication for You
This page is intended to explain differences between oral naltrexone, FDA-approved extended-release injectable naltrexone and sustained-release implant formulations. It does not determine which medication or treatment model is appropriate for an individual patient.
Do not stop opioids, discontinue methadone or buprenorphine, begin naltrexone, alter prescribed medication or attempt opioid withdrawal based solely on this page. Antagonist treatment requires individual medical assessment and safe preparation.
Suspected overdose, severe withdrawal, loss of consciousness, abnormal breathing or another medical emergency requires immediate local emergency assistance.