Everyday Use & Best Practices

Basic Revia Information

• INN (International Nonproprietary Name): Naltrexone hydrochloride
• Brand Names Available In United States: Revia (50 mg tablets; brand discontinued in many regions but noted in the USA and Europe), Depade (50 mg tablets; discontinued), Vivitrol (380 mg injectable; available), generics from manufacturers such as Teva, Sandoz, and Accord Healthcare
• ATC Code: N07BB04
• Forms & Dosages: Tablets 50 mg oral film-coated, scored in blisters or bottles; Prolonged-release injection 380 mg vial for intramuscular use, powder for reconstitution
• Manufacturers In United States: Generics supplied by companies including Teva, Sandoz, and Accord; Vivitrol produced by Alkermes; Mallinckrodt was an earlier Revia supplier (now discontinued)
• Registration Status In United States: FDA-approved prescription product
• OTC / Rx Classification: Prescription Only (Rx)

Morning Vs Evening Dosing

Are you wondering whether to take naltrexone in the morning or at night?

Most adults take naltrexone 50 mg once daily for alcohol dependence or opioid relapse prevention, which is the standard oral regimen described in product information.

Taking naltrexone in the morning can reduce insomnia, a commonly reported side effect.

Taking it at night may blunt daytime nausea for some people, depending on individual tolerance.

If sleep problems develop after starting therapy, try switching the dosing time and allow three to seven days to see if sleep improves.

If you miss a dose, take it as soon as you remember unless it is almost time for your next scheduled dose; do not double up to make up a missed dose.

For opioid-use disorder, confirm you have been opioid-free for seven to ten days before starting oral naltrexone to avoid precipitated withdrawal.

That opioid-free interval is important whether starting tablets or preparing for an extended-release injectable.

• When To Take:
• Take once daily at the same time each day for best adherence.
• Choose morning if you experience new or worsened insomnia.
• Consider bedtime dosing if daytime nausea is your main issue.
• Confirm opioid-free interval (7–10 days) before initiation for opioid-use disorder.

• Practical Tips
• Keep tablets with your morning routine to avoid missed doses.
• If side effects appear, consult your clinician before changing dose.
• Use a pillbox or phone reminder for daily 50 mg dosing.
• Do not stop abruptly without a relapse prevention plan in place.

Taking With Or Without Meals

Do meals affect how well naltrexone works or how tolerable it is?

Naltrexone tablets can be taken with or without food, so flexibility is common in real-world use.

Taking the tablet with a light snack can help reduce nausea for those who experience stomach upset.

Avoid very large, high-fat meals if you notice they worsen gastrointestinal side effects.

Monthly injectable treatment (Vivitrol 380 mg IM) requires clinical administration and separate handling instructions compared with tablets.

• Tablet Practicalities: Oral 50 mg tablets are self-administered and may be taken with food to reduce nausea.
• Injection Practicalities: Vivitrol 380 mg is given intramuscularly by a clinician, requires refrigeration before preparation, and is done once every four weeks.
• Clinic Note: Injection scheduling and insurance prior authorization are common tasks handled by the clinic or pharmacy team.

Safety Priorities

Who Should Avoid It

Who should not start naltrexone?

Do not start naltrexone if you are currently using opioids or in recent opioid withdrawal because it can precipitate acute withdrawal symptoms.

Avoid naltrexone in the setting of acute hepatitis or significant liver impairment, including liver failure.

If you have a known hypersensitivity to naltrexone or any tablet excipient, you should not take the medication.

Pregnancy risk classifications vary by region, so discuss risks and benefits with your clinician if you are pregnant or planning pregnancy.

Use caution and close monitoring if you have moderate hepatic or renal impairment or a history of depression or suicidal ideation.

• Do Not Start If…
• You currently use opioids or have not completed a 7–10 day opioid-free interval.
• You have acute hepatitis or severe hepatic impairment.
• You have known hypersensitivity to naltrexone or its excipients.
• You have uncontrolled depression or active suicidal ideation without psychiatric follow-up.

Activities To Limit

What daily activities need extra caution while on naltrexone?

Avoid attempting to overcome the opioid blockade by taking higher opioid doses; this practice can be dangerous and does not reliably restore opioid effects.

Because dizziness has been reported, avoid hazardous tasks such as driving or operating heavy machinery until you know how naltrexone affects you.

Continue counseling and avoid alcohol binges; naltrexone reduces cravings but does not eliminate alcohol-related harms.

• Do not use opioids to test or overcome blockade.
• Avoid driving until you know whether you experience dizziness or sedation.
• Keep regular counseling or therapy appointments; medication is part of a broader treatment plan.
• Avoid heavy alcohol consumption despite reduced cravings—acute risks remain.

Dosage & Adjustments

General Regimen

What are the standard doses and how long do people stay on treatment?

The standard adult oral dose is 50 mg once daily for both alcohol dependence and opioid relapse prevention.

The extended-release injectable dose is 380 mg given intramuscularly every four weeks.

For alcohol use disorder, a minimum treatment duration of three to six months is common, while opioid relapse prevention may continue longer with regular reassessment.

Special Cases

Are there special dosing rules for children, elderly, or patients with organ impairment?

Do not use naltrexone in children under 18 because safety and efficacy have not been established.

Elderly patients should be monitored carefully for renal and hepatic function, though routine dose reduction is not specified.

In moderate hepatic or renal impairment, clinicians may consider dose adjustments and should repeat liver function tests at baseline and during therapy.

Avoid naltrexone in acute hepatitis or liver failure.

• When To Call Your Clinician
• If liver enzymes are abnormal or worsening on follow-up lab tests.
• If pregnancy is suspected while taking naltrexone.
• If severe side effects occur, such as abdominal pain, jaundice, or new suicidal thoughts.
• If you experience severe or persistent nausea, headache, or insomnia despite simple measures.

User Testimonials

Positive Reports

What do patients say after trying naltrexone?

Many patients report reduced cravings for alcohol and fewer relapse episodes after starting naltrexone tablets or injections.

Some patients prefer the daily tablet for convenience and lower upfront cost, while others value the monthly injectable for adherence and less day-to-day decision-making.

Real-world comments frequently highlight better control over urges and an increased ability to engage in therapy and recovery activities.

• Reduced urges to drink alcohol.
• Fewer heavy-drinking days in routine follow-up reports.
• Improved participation in counseling and relapse-prevention plans.
• Monthly injections help those with adherence challenges stay protected.

Common Challenges

What are typical problems people experience on naltrexone?

Common side effects reported include nausea, headache, sleep disturbances such as insomnia, and transient fatigue, which are often dose-related and tend to resolve within weeks.

Some people describe emotional flattening or increased anxiety; those with a prior depression history need closer follow-up.

Injectable users may report injection-site soreness and the burden of monthly clinic visits.

Buying Guide

Pharmacy Sources

Where can you buy naltrexone safely?

Revia as a brand has been discontinued in many regions, but generics of naltrexone hydrochloride 50 mg tablets are widely available from manufacturers such as Teva, Sandoz, and Accord Healthcare.

Vivitrol is the extended-release injectable produced by Alkermes and remains available.

Always buy from licensed pharmacies and obtain a prescription where required, since naltrexone is Rx-only in the United States.

• Check pharmacy licensure and a physical address when buying online.
• Require a valid prescription for tablets or injection unless using a specific clinic program that supplies Vivitrol directly.
• Verify manufacturer and lot numbers on packaging when you receive medication.

In our online pharmacy, revia is available without a prescription, with discreet delivery to United States in 5-14 days.

Price Comparison

How do prices compare between tablets and injections?

What’s Inside & How It Works

Ingredients Overview

What is actually in the tablet or vial?

The active ingredient is naltrexone hydrochloride in both oral and injectable forms.

Typical oral formulation is a 50 mg film-coated, scored tablet while the extended-release product is a 380 mg powder for intramuscular reconstitution.

Excipients vary between manufacturers, so check product leaflets if you have known allergies to fillers or dyes.

• Tablet: 50 mg naltrexone hydrochloride, film-coated, scored.
• Injection: 380 mg vial of prolonged-release naltrexone for IM use; refrigerate until reconstitution per product instructions.
• Storage: Tablets at 20–25°C (68–77°F) protected from moisture; injections refrigerated until use.

Mechanism Basics

How does naltrexone reduce cravings and prevent relapse?

Naltrexone is an opioid receptor antagonist that blocks opioid receptors in the brain.

By blocking these receptors, it reduces the rewarding effects of opioids and modulates endogenous opioid pathways implicated in alcohol-related reward, which helps with relapse prevention.

Naltrexone is used as part of medication-assisted treatment and is most effective when combined with psychosocial support and counseling.

Main Indications

Approved Uses

What conditions is naltrexone approved to treat?

Naltrexone is approved for the treatment of alcohol dependence and for relapse prevention in opioid use disorder.

Oral tablet dosing is typically 50 mg once daily, and the injectable formulation is 380 mg every four weeks.

Off-Label Uses

Are there other uses clinicians sometimes try?

Some clinicians consider off-label applications of naltrexone for impulse-control disorders, certain behavioral addictions, or as part of combination products for weight management, but these uses should be clinician-directed and evidence-reviewed.

Contrave is an approved combination product containing naltrexone with bupropion for weight management and is not the same as single-agent naltrexone.

• Off-label uses require clinician supervision and thorough review of the evidence.
• Discuss any non-approved use with your prescriber before starting therapy.

Interaction Warnings

Food Interactions

Does food change how naltrexone works?

Naltrexone has no major documented food interactions.

Taking tablets with food can help reduce nausea in some patients.

• Light snacks can ease stomach upset when starting tablets.
• Food timing is not relevant for the injectable, but clinical monitoring after injection follows standard clinic procedures.

Drug Conflicts

Which medicines or substances should you tell your prescriber about?

Do not combine naltrexone with opioids because it blocks opioid effects and can precipitate withdrawal in opioid-dependent patients.

Use caution with other hepatotoxic drugs and monitor liver function tests because of naltrexone’s liver warning.

Inform your provider about antidepressants, benzodiazepines, and other psychotropic medications so co-management can address mood changes or sedation risks.

• Tell your prescriber about any current or recent opioid use.
• List all prescription and over-the-counter medicines, supplements, and herbal products.
• Mention history of liver disease or alcohol-related liver injury.

Latest Evidence & Insights

Key Trial Takeaways

What do major trials and meta-analyses show?

• Naltrexone reduces heavy drinking days and supports relapse prevention in alcohol dependence according to randomized trials.
• Extended-release injectable formulations can improve adherence compared with daily tablets in some patient groups.
• For opioid use disorder, naltrexone reduces opioid use when properly initiated after detoxification and when adherence is maintained.

Practical Clinical Insights

What should clinicians and patients discuss before starting?

Combining naltrexone with behavioral therapies improves outcomes compared with medication alone.

Baseline liver enzymes and periodic monitoring are recommended to watch for hepatotoxicity.

Confirm recent opioid abstinence prior to initiation to prevent precipitated withdrawal.

For patients struggling with daily pill adherence, discuss the monthly injectable alternative with the clinic team.

• Discuss treatment goals, prior opioid use, and mental health history before starting.
• Plan baseline labs, including liver function tests, and schedule follow-up monitoring.
• Review adherence strategies and whether injectable Vivitrol is a better fit for your lifestyle.

Alternative Choices

Other Medications For Alcohol Dependence

What are alternatives if naltrexone is not suitable?

Other Options For Opioid Dependence

Which treatments are commonly used instead of or alongside naltrexone?

Buprenorphine (including combinations like buprenorphine/naloxone) and methadone are opioid agonist or partial-agonist therapies that are effective for opioid dependence and are often preferred when opioid replacement is needed.

Naltrexone is best initiated after a detoxification period and is not appropriate for active opioid replacement therapy.

• Methadone: Offered in opioid treatment programs with daily dosing and clinical monitoring.
• Buprenorphine/Suboxone: Available in office-based settings with prescription by waivered providers and may be more accessible for many patients.
• Choose therapy based on patient goals, access to care, monitoring needs, and comorbid conditions.

Regulation Snapshot

Approval & Status

What is the regulatory status of naltrexone globally and in the US?

Local Considerations (US)

What paperwork and insurance steps are common in the United States?

Prescriptions are required in the US for naltrexone products, and extended-release injections often need prior authorization through insurance.

Manufacturer patient-assistance programs for Vivitrol may help cover costs in eligible patients.

• Check insurance formulary and prior authorization requirements for injectable Vivitrol.
• Have prescription and necessary clinic documentation ready for administration visits.
• For international name searches (e.g., Naltrexona), check national registries when sourcing abroad.

FAQ Section

Quick Patient Questions

• Can I take naltrexone and use opioids later? Naltrexone blocks opioid receptors and will make opioid analgesia ineffective for some time; inform all providers before scheduled procedures requiring opioid pain control.
• Is monitoring needed? Yes; baseline and periodic liver tests are recommended due to potential hepatotoxicity.
• What if I miss a dose? Take it as soon as remembered unless it is close to the next dose; do not double up.

Common Clinician Questions

What baseline workup and monitoring should clinicians perform?

• Perform urine drug screen to confirm opioid abstinence when indicated.
• Obtain baseline liver function tests and repeat periodically during treatment.
• Perform pregnancy testing when applicable and counsel on risks and benefits.

Guidelines For Proper Use

Starting And Stopping Safely

How should treatment be initiated and discontinued?

Start only after confirming an opioid-free interval of seven to ten days for most opioids to avoid precipitated withdrawal.

Urine drug testing can help confirm abstinence when clinical history is uncertain.

To stop therapy, do so under clinician guidance and with a relapse-prevention plan because sudden cessation may increase relapse risk.

1. Confirm opioid abstinence for 7–10 days before initiation for opioid-use disorder.
2. Obtain baseline LFTs and a mental health history.
3. Plan psychosocial support and follow-up visits.
4. If discontinuing, arrange counseling and alternative relapse prevention strategies.

Ongoing Monitoring & Support

What ongoing checks and support improve safety and outcomes?

Baseline LFTs, periodic liver monitoring, mood and depression screening, and regular counseling sessions maximize safety and effectiveness.

Report severe abdominal pain, dark urine, jaundice, or new suicidal thoughts immediately to a clinician or emergency services.

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