Naltrexone: MedlinePlus Pharmaceuticals (2023)

Pronounced like (nal trex' uno)

  • Why is this medicine prescribed?
  • How should I use this medicine?
  • Other uses of this medicine
  • What special precautions should I take?
  • What special dietary guidelines should I follow?
  • What if I miss a dose?
  • What side effects can this drug cause?
  • What should I know about storing and disposing of this medicine?
  • In case of emergency/overdose
  • What other information should I know?
  • brand

Important warning:

Taking high doses of naltrexone can cause liver damage. Naltrexone is unlikely to cause liver damage when taken at the recommended dose. Tell your doctor if you have or have ever had hepatitis or liver disease. Stop taking naltrexone and see your doctor right away if you experience any of the following symptoms: extreme tiredness, unusual bleeding or bruising, loss of appetite, pain in the upper right side of your stomach that lasts more than a few days, light colored bowel movements, dark urine or skin or yellowing of the eyes.

Keep all appointments with your doctor and lab. Your doctor may order certain lab tests to check how your body is responding to naltrexone.

Discuss the risks of taking naltrexone with your doctor.

(Video) Low Dose Naltrexone (Surprising Inflammation Drug)

Why is this medicine prescribed?

Naltrexone is used with counseling and social support to help people who have stopped drinking and are using street drugs to continue to avoid drinking or using drugs. Naltrexone should not be used to treat people who continue to use illegal drugs or drink heavy alcohol. Naltrexone belongs to a class of drugs called opioid antagonists. It works by reducing the desire for alcohol and blocking the effects of opioids and opioid street drugs.

Naltrexone is available as a tablet that can be taken by mouth at home or under supervision at a clinic or treatment center. When naltrexone is taken at home, it is usually taken once a day with or without food. When you take naltrexone in a clinic or treatment center, you can take it once a day, every other day, every three days, or every day except Sunday. Follow the directions on the prescription label carefully and ask your doctor or pharmacist to explain any part you do not understand. Take naltrexone exactly as directed. Do not take more or less or more often than prescribed by your doctor.

Naltrexone is only useful when used as part of an addiction treatment plan. It is important to attend all counseling sessions, support group meetings, educational programs, or other treatments recommended by your doctor.

Naltrexone will help you avoid drug and alcohol abuse, but it will not prevent or relieve the withdrawal symptoms that may occur when you stop using these substances. Conversely, naltrexone can cause or worsen withdrawal symptoms. You should not take naltrexone if you have recently stopped using an opioid or opioid street drug and are now experiencing withdrawal symptoms.

Naltrexone will help you avoid drugs and alcohol only while you are taking it. Keep taking naltrexone even if you feel well. Do not stop taking naltrexone without talking to your doctor.

Other uses of this medicine

This medicine can sometimes be used for other purposes; ask your doctor or pharmacist for more information.

(Video) The Many Uses of Low-Dose Naltrexone (LDN)

What special precautions should I take?

Before taking naltrexone,

  • Tell your doctor and pharmacist if you are allergic to naltrexone, naloxone, any other opioids, or any other medications.
  • Tell your doctor if you are taking opioids (narcotics) or street drugs, including levomethadone acetate (LAAM, ORLAAM) (not available in the U.S.) or methadone (Dolophine, Methadose), and certain treatments for diarrhea , the cough or the painkiller. Also tell your doctor if you have taken any of these medicines in the past 7 to 10 days. If you are not sure whether a drug you are taking is an opioid, talk to your doctor. Your doctor may order certain tests to determine if you have taken opioids or used opioid street drugs in the past 7 to 10 days. Your doctor may tell you not to take naltrexone if you have taken or used opioids in the past 7 to 10 days.
  • Do not take opioid medications or use opioid street drugs while you are being treated with naltrexone. Naltrexone blocks the effects of opioids and opioid street drugs. If you take or use these substances in low or normal doses, you may not feel their effects. Taking or using higher doses of opioids or drugs during treatment with naltrexone can cause serious injury, coma (loss of consciousness for a long time), or death.
  • You should be aware that if you have taken opioid medications before treatment with naltrexone, you may become more sensitive to the effects of these medications after treatment ends. After you finish your treatment, tell any prescribing doctor that you have taken naltrexone in the past.
  • Tell your doctor about other prescription and over-the-counter medicines, vitamins, dietary supplements, and herbal products you are taking or plan to take. Be sure to mention disulfiram (Antabuse) and thioridazine. Your doctor may need to change the dose of your medication or monitor you carefully for side effects.
  • Tell your doctor if you have or have had depression or kidney disease.
  • Tell your doctor if you are pregnant, plan to become pregnant or are breast-feeding. Call your doctor if you become pregnant while taking naltrexone.
  • If you need medical treatment or surgery, including dental surgery, tell your doctor or dentist that you are taking naltrexone. Wear or bring your medical certificate so that the health care provider who treats you in an emergency knows that you are taking naltrexone.
  • Be aware that people who abuse drugs or alcohol often become depressed and sometimes attempt to harm or kill themselves. Taking naltrexone will not reduce your risk of trying to harm yourself. If you or a family member are experiencing symptoms of depression such as sadness, anxiety, hopelessness, guilt, worthlessness or helplessness, or if you are thinking or planning or trying to harm or kill yourself. Make sure your family knows what symptoms can be serious so they can contact a doctor right away if you can't seek treatment on your own.

What special dietary guidelines should I follow?

Continue with your normal diet unless otherwise directed by your doctor.

What if I miss a dose?

Take the missed dose as soon as you remember. However, if it is almost time for your next dose, skip the missed dose and continue with your regular medication schedule. Do not take a double dose to make up for a missed dose.

What side effects can this drug cause?

Naltrexone can cause side effects. Tell your doctor if any of these symptoms are severe or persist:

  • motion sickness
  • Vomit
  • stomach pain or cramps
  • diarrhea
  • constipate
  • Anorexia
  • Headache
  • Dizziness
  • worry
  • nervous
  • irritable
  • scream
  • difficulty falling asleep or staying asleep
  • increasing or decreasing energy
  • drowsiness
  • muscle or joint pain
  • skin rash

Some side effects can be serious. Call your doctor right away if you experience any of these symptoms or those listed in the Important Warnings section:

  • Confused
  • Hallucinations (seeing things or hearing sounds that aren't there)
  • blurred vision
  • severe vomiting and/or diarrhoea

Naltrexone can cause other side effects. Call your doctor if you experience any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor can submit a report online to the US Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting Program ( or by phone (1-800-332-1088).

(Video) Drug used for Opiate addiction, Naltrexone, now used for Cancer

What should I know about storing and disposing of this medicine?

Keep this medicine in the original container, tightly closed and out of the reach of children. Store at room temperature away from excessive heat and humidity (not in the bathroom).

It is important to keep all medicines out of the sight and reach of children, as many packages (such as weekly pill reminders, eye drops, creams, patches and inhalers) are not suitable for children and can be easily opened by young children. To protect young children from poisoning, always keep hard hats away and immediately place the medicine in a safe place, one side up, out of sight and away.

Unnecessary medications should be handled specifically to ensure that pets and children cannot eat them. However, you should not flush this medicine down the toilet. Instead, the best way to dispose of drugs is through a drug withdrawal program. Talk to your pharmacist or contact your local waste/recycling department to find out about recycling programs in your community. Check out the FDA's Safe Disposition of Medicines website ( for more information (if you do not have access to the returns program).

In case of emergency/overdose

In case of overdose, call the Poison Control Helpline at 1-800-222-1222. Information is also available online at the victim collapses, has a seizure, has trouble breathing, or cannot wake up, call 911 immediately.

(Video) Doctor Explains What Naltrexone Is? Vivitrol For Addiction Substance Abuse

What other information should I know?

Before having any lab tests, tell your doctor and the lab staff that you are taking naltrexone.

If you have any questions about naltrexone, ask your doctor or pharmacist.

It is important to keep a written list of all prescription and over-the-counter medications and any products (such as vitamins, minerals, or other dietary supplements) that you take. You should take this checklist with you every time you visit your doctor or are admitted to hospital. It is also important information to have with you in case of an emergency.

(Video) What You Need to Know About Low Dose Naltrexone


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Last Comment -15/10/2017

Explore Drugs and Narcotics


Naltrexone: MedlinePlus Pharmaceuticals? ›

Naltrexone is in a class of medications called opiate antagonists. It works by decreasing the craving for alcohol and blocking the effects of opiate medications and opioid street drugs.

Why don t more doctors prescribe naltrexone? ›

There are several reasons for underutilization of naltrexone, O'Brien and other experts told Psychiatric News: for example, many physicians are unfamiliar with the medication, and alcohol rehabilitation centers are not typically staffed by medical professionals.

What pharmaceutical company makes naltrexone? ›

Naltrexone 50 mg | Mallinckrodt Pharmaceuticals.

Is naltrexone FDA approved? ›

Naltrexone is an opioid antagonist used to treat alcohol use disorder and opioid dependence. It is FDA-approved for alcohol use disorder and opioid dependence treatment.

Can any prescriber offer naltrexone? ›

Who can prescribe naltrexone? can prescribe medications, such as physicians, nurse practitioners, physician assistants, can prescribe naltrexone and can do so in any type of setting. provider or program who is more experienced in treating opioid use disorder.

What is the controversy with naltrexone? ›

Naltrexone therapy is controversial because its use conflicts with the view of abstinence held by Alcoholics Anonymous and most medical treatment programs.

What is the danger of naltrexone? ›

You could overdose and develop serious problems. This medicine may cause serious problems with your liver. Call your doctor right away if you start having dark urine, pain in the upper stomach, or yellowing of the eyes or skin while you are using this medicine. This medicine may increase thoughts of suicide.

What drugs should not be taken with naltrexone? ›

The most dangerous naltrexone interaction is with opioids. This includes cough medications and antidiarrheals that contain opioids. This interaction can lead to opioid withdrawal symptoms. Talk to your healthcare provider and pharmacist if you take naltrexone.

What is the alternative to naltrexone? ›

  • Vivitrol.
  • Disulfiram.
  • Ondansetron.
  • Gabapentin.
  • Spironolactone.
  • Gabapentin enacarbil.

What is the new use for naltrexone? ›

Though physicians previously prescribed Naltrexone to treat opioid addictions, they now are employing the drug in off-label uses to aid patients with conditions ranging from pain and a dysfunctional immune system, to inflammation, cancer, and mental health issues.

Is naltrexone covered by insurance? ›

It is available in generic and brand versions. Generic naltrexone covered by most Medicare and insurance plans, but some pharmacy coupons or cash prices may be lower. Compare opioid antagonists.

When do doctors prescribe naltrexone? ›

Naltrexone is used to help narcotic dependents who have stopped taking narcotics to stay drug-free. It is also used to help alcoholics stay alcohol-free. The medicine is not a cure for addiction.

Why do dermatologists prescribe naltrexone? ›

Primarily, it is used for pain control, including both chronic pain and inflammation control.

Who can prescribe naltrexone in us? ›

Any licensed healthcare provider in the United States who is authorized to write a prescription can legally prescribe naltrexone. Naltrexone may be prescribed via a telehealth or virtual appointment with a clinician, or during an in-person office visit.

How long can you take naltrexone? ›

Most people take the medicine for 12 weeks or more. Naltrexone only has to be taken once a day. Be sure to take naltrexone just the way your doctor tells you to. Don't take extra pills, don't skip pills and don't stop taking pills until you talk to your doctor.

Does naltrexone really work for alcoholism? ›

Among approved medications, daily naltrexone and long-acting injectable naltrexone have perhaps the strongest evidence for their use. They have been shown to improve numerous drinking outcomes, including a return to any drinking and a return to heavy drinking (5).

Why do I feel good on naltrexone? ›

Naltrexone is used for the treatment of opioid use disorder or alcohol use disorder. This type of treatment is called medication-assisted treatment (MAT). Opioids act on brain receptors called opioid receptors. When these receptors are activated, they cause the pleasurable symptom called euphoria.

How bad is naltrexone for your liver? ›

Naltrexone may cause liver damage when taken in large doses. It is not likely that naltrexone will cause liver damage when taken in recommended doses. Tell your doctor if you have or have ever had hepatitis or liver disease.

What is the success rate of naltrexone? ›

This trial showed that in patients who received medical treatment but not behavioral therapy, naltrexone (at a dose of 100 mg daily), given for 16 weeks, was more efficacious than placebo in increasing the percentage of days of abstinence (80.6% vs. 75.1%) and in reducing the risk of a heavy-drinking day (66.2% vs.

Why do I feel weird on naltrexone? ›

This medicine may cause some people to become dizzy, drowsy, or less alert than they are normally. If any of these side effects occur, do not drive, use machines, or do anything else that could be dangerous if you are dizzy or are not alert while you are taking naltrexone.

What are the long term side effects of naltrexone? ›

Additionally, although naltrexone is generally regarded as safe for long-term use, there are a few long-term side effects of naltrexone (e.g., arthritis, liver damage and respiratory infections).

Does naltrexone block happiness? ›

In alcohol use disorder, naltrexone works indirectly by blocking endorphins. There will be no euphoria.

Why does naltrexone have to be taken at night? ›

Studies show that low-dose Naltrexone may relieve pain and symptoms of chronic fatigue syndrome. It achieves this by suppressing the release of chemicals (cytokines) that cause pain. So, people with chronic fatigue syndrome may sleep more comfortably if they take Naltrexone before bed.

Can you drink caffeine on naltrexone? ›

Caffeine use was unaffected by naltrexone.

Can naltrexone be taken on an as needed basis? ›

Taking naltrexone on an as-needed basis rather than as a daily dose may be more tolerable for some people because it allows their dopamine levels to recover in between uses. The approach could also let people feel more in control of their treatment.

Is there a natural version of naltrexone? ›

PhenQ ~ Top-rated OTC Naltrexone Alternative

PhenQ is made of 5 potent ingredients that are 100% natural. These ingredients are Chromium Picolinate, Capsimax Powder, Caffeine, Nopal and L-Carnitine Fumarate. These ingredients are known to target the major cause of stubborn and unwanted fat in the body.

Does naltrexone block all dopamine? ›

Naltrexone blocks the dopamine release in response to drinking. The most profound effects start at one hour after taking the medicine. The effects diminish over time which requires some patients to repeat dosing anywhere from 6 - 10 hours if they have a prolonged drinking episode.

Which is the least common side effects of naltrexone? ›

Less common side effects include:
  • feeling energetic.
  • loss of appetite.
  • thirst.
  • diarrhoea, constipation.
  • depression and irritability.
  • dizziness.
  • skin rashes.
  • decreased potency, delayed ejaculation.

Is naltrexone an opioid substitute? ›

Naltrexone is prescribed in treating Opioid addictions. It blocks the harmful effects of Opioids, which reduces future drug cravings and urges. Since it may trigger withdrawal symptoms, Naltrexone should only be taken 7-10 days after your last drug use.

What is the price of naltrexone tablets? ›

Generic Revia (Naltrexone) 50mg Tablet at Rs 800/stripe | Gautam Budh Nagar | Noida | ID: 22455159762.

What is generic for naltrexone? ›

Naltrexone (Vivitrol) is available as a generic medication and may be significantly cheaper compared to the brand version. Unless there is a specific reason you need the brand, the generic medication will be a better value.

How much is a shot of naltrexone? ›

The drug, extended-release Naltrexone, is injected once a month, and costs about $1,100 per injection.

Does naltrexone have to be taken at night? ›

Bottom Line. The manufacturer does not specify if you should take naltrexone tablets in the morning or at night. Take naltrexone exactly as your doctor orders. Many patients take their medication in the morning to help affirm their continued treatment success for either opioid use disorder or alcohol use disorder.

Is naltrexone safe for elderly? ›

Naltrexone should be used with caution in older patients, especially those with preexisting hepatic disease.

What is naltrexone used for autoimmune? ›

It regulates the immune system by promoting T regulatory cell function. The T regulatory cells, or Tregs, keep the immune system in balance, and they turn inflammation on and off, depending on what's needed.

Does naltrexone help with mental health? ›

Low Dose Naltrexone is an opioid antagonist medication licensed for the management of drug and alcohol dependency. It's showing promising results as an off-label treatment for chronic pain. It also helps with several other conditions such as Chronic Fatigue Syndrome and even Anxiety and Depression.

Does naltrexone calm immune system? ›

LDN works by increasing the body's release of endorphins, which helps moderate the immune system. This can decrease the immune system's inflammatory response to your body's healthy tissues.

What is the percentage of success for naltrexone? ›

During the study, 39% of patients abstained, while of the individuals reporting drinking at baseline, 86% were consuming less alcohol by their final visit.

Why don t doctors prescribe LDN? ›

Because this is an old, inexpensive generic medication, pharmaceutical companies have no incentive to conduct research on it. Consequently, large, well-controlled clinical trials of low-dose naltrexone (LDN) are scarce. That may be why your doctor is reluctant to prescribe it.

What is the success rate of naltrexone for alcoholism? ›

This trial showed that in patients who received medical treatment but not behavioral therapy, naltrexone (at a dose of 100 mg daily), given for 16 weeks, was more efficacious than placebo in increasing the percentage of days of abstinence (80.6% vs. 75.1%) and in reducing the risk of a heavy-drinking day (66.2% vs.

Who is a candidate for naltrexone? ›

Will naltrexone work for me? Naltrexone, an FDA-approved medication that prevents the relapse to opioid dependence, is available to patients who have achieved complete detoxification from opioids. Patients must be opioid-free for at least seven to 10 days to avoid sudden withdrawal symptoms.

How long can you be on naltrexone for? ›

Most people take the medicine for 12 weeks or more. Naltrexone only has to be taken once a day. Be sure to take naltrexone just the way your doctor tells you to. Don't take extra pills, don't skip pills and don't stop taking pills until you talk to your doctor.

How long are patients on naltrexone? ›

Treatment Duration and Discontinuing Oral Naltrexone

The FDA label states that naltrexone should be taken for up to 3 months to treat AUDs. Healthcare providers should tailor the length of treatment to individual patients.

What should I avoid while taking naltrexone? ›

People using naltrexone should not:
  • use ANY opioid (for example: heroin, morphine, codeine, oxycodone, tramadol, hydrocodone or other prescription or illegal opioids)
  • use illicit drugs.
  • drink alcohol.
  • take CNS depressants such as sedatives, tranquilizers, or other drugs.
Jul 25, 2022

Is LDN hard on the liver? ›

Even at high doses of 50mg - 100mg it does not cause harm to the liver. Low dose naltrexone will not cause damage to the liver. Even those with mild to moderate liver damage can safely metabolize low dose naltrexone.

Who should not take LDN? ›

Because LDN blocks opioid receptors throughout the body for three or four hours, people using medicine that is an opioid agonist, i.e. narcotic medication — such as Ultram (tramadol), morphine, Percocet, Duragesic patch or codeine-containing medication — should not take LDN until such medicine is completely out of ...

What is the most effective treatment for alcohol dependence? ›

Cognitive-behavioral therapy (CBT) helps to identify feelings and situations that can lead to heavy drinking and teaches coping skills and stress management techniques to change the thoughts that cause a desire to drink.

When should I take naltrexone morning or night? ›

Official answer. Most patients take their naltrexone tablet in the morning, but the manufacturer does not specify a certain time of the day. Some patients feel taking naltrexone in the morning after breakfast is a good reminder of their continued treatment commitment for opioid use disorder or alcohol use disorder.

Does LDN give you energy? ›

LDN increases dopamine levels. Dopamine is a neurotransmitter that makes us feel happy and rewarded, gives us energy and helps our brain solve problems.


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