Understanding Naltrexone: A Medication for Alcohol Use Disorder

Cutting back on alcohol or quitting entirely can be challenging, especially for those who have developed regular drinking patterns or physical dependence. While behavioral treatments, support groups, and therapy are valuable for addressing alcohol misuse, medications can sometimes enhance their effectiveness. Naltrexone is one such medication proven to help reduce cravings and support sobriety.

In this article, we'll explore what naltrexone is, how it works, and discuss additional treatment options that can complement naltrexone therapy.

What Is Naltrexone?

Also known as Vivitrol, naltrexone is a widely used medication for moderate to severe alcohol use disorder (AUD). It's available as a daily oral tablet or a monthly injection.

Naltrexone was first developed in 1963 and received FDA approval in 1984 for treating heroin addiction. A decade later, it was approved for alcohol misuse after research showed it could mediate alcohol's effects, reducing cravings and relapse rates.

Multiple studies have confirmed its effectiveness. Recent research found that naltrexone significantly reduces binge drinking among men with mild to moderate alcohol use disorder. Additional studies demonstrated that combining naltrexone with counseling led to greater reductions in heavy drinking compared to counseling alone.

How Does Naltrexone Work?

Naltrexone works by targeting the brain's opioid system, which is part of our reward pathway. This system plays a crucial role in how we experience pleasure and satisfaction.

Alcohol stimulates the brain's reward pathway, releasing chemicals that create feelings of pleasure and euphoria. This triggers opioid receptors, creating the satisfying sensation that makes drinking appealing. This pleasure-reward cycle can encourage repeated alcohol use, potentially leading to misuse or dependence.

Naltrexone is an "opioid antagonist" that blocks these opioid receptors. Think of it as a key that fits into a lock but doesn't turn it. By occupying these receptors, naltrexone prevents alcohol from triggering the release of pleasure-inducing chemicals. Even if alcohol is consumed, the expected rewarding effects are diminished or absent because naltrexone is blocking the brain's access points.

It's important to understand that while naltrexone helps manage alcohol cravings, it doesn't cure alcohol dependence. Overcoming alcohol misuse requires addressing more than just physical cravings. However, by disrupting the reward mechanism associated with alcohol, naltrexone provides a valuable tool in comprehensive treatment plans.

How Long Does Naltrexone Block Alcohol?

The duration of naltrexone's effects depends on the form taken. Oral naltrexone typically lasts 24 to 72 hours, while injections can provide coverage for about a month. This means reduced alcohol cravings for several days with the pill version, or approximately a month with the injection.

Naltrexone is processed by the liver, and how quickly it's metabolized depends on factors like age and overall health. Older individuals typically process medications more slowly, and underlying organ diseases can affect processing speed.

Naltrexone begins working immediately after administration. People typically experience relief from alcohol cravings within one to two hours of taking it.

Naltrexone Side Effects

Naltrexone is generally well-tolerated and non-addictive. Common side effects include:

• Nausea, vomiting, or chills
• Diarrhea or constipation
• Headache, dizziness, or ringing in the ears
• Muscle or joint pain
• Reduced appetite
• Trouble sleeping
• Anxiety or restlessness
• Bruising, itching, or swelling at injection sites

Rare but serious side effects may include:

• Increased blood pressure or heart rate
• Liver function changes or liver failure
• Depressed mood or suicidal thoughts
• Severe allergic reactions
• Pneumonia

When Should You Start Taking Naltrexone?

Doctors typically recommend waiting until acute alcohol withdrawal symptoms have subsided before starting naltrexone. It's generally advised to complete the detox process first to prevent severe withdrawal symptoms or side effects.

Research indicates naltrexone works best for people who have stopped drinking for at least four days before beginning treatment. Being abstinent from alcohol when starting naltrexone may reduce medication side effects, particularly nausea.

Experts recommend using naltrexone as part of a comprehensive treatment plan. This approach helps people develop additional tools to maintain sobriety after discontinuing the medication.

Naltrexone is typically tapered off after three to six months, though healthcare professionals might recommend continuing for at least one year since benefits may be lost when the medication is stopped. Long-term use of naltrexone is considered safe when used as directed.

What Form of Naltrexone Should You Take?

Only a medical professional can determine the appropriate form and dosage for your situation. Typically, doctors prescribe a 25mg oral tablet as a test dose to ensure tolerance. If well-tolerated, the dosage may increase to 50mg daily. Taking naltrexone tablets with food can help reduce nausea or stomach upset.

For injections, the standard dose is 380mg administered intramuscularly once monthly by a doctor, nurse, or pharmacist.

What Should You Avoid While Taking Naltrexone?

Since naltrexone is designed to reduce alcohol cravings, it's important to avoid drinking alcohol while taking it. You should also avoid illegal drugs and opioid pain medications (such as codeine, hydrocodone, oxycodone, or morphine) since naltrexone blocks opioids' effects. Attempting to overcome this blocking effect by taking large amounts of opioids could lead to overdose, serious injury, coma, or death.

Some cough syrups contain opioid medications, so discuss all medicines with your healthcare provider. Pregnant women should not take naltrexone due to unknown effects on the fetus, and breastfeeding while taking the medication is not recommended since it can pass into breast milk.

Additional Treatment Options for Alcohol Misuse

Since naltrexone works best as part of a comprehensive treatment plan, consider these additional approaches:

• Support Groups: Programs like Alcoholics Anonymous (AA) provide social connection and practical advice for maintaining sobriety. Studies show these groups help build confidence in avoiding alcohol and support long-term recovery.
• Behavioral Therapy: Individual, group, or family therapy can help identify root causes of substance misuse, repair relationships, and develop coping skills. Cognitive behavioral therapy (CBT) is particularly effective for substance misuse.
• Residential Treatment: Both inpatient and outpatient facilities provide intensive treatment. Inpatient programs require staying at a facility for 30-90 days for detox, therapy, and medication, while outpatient treatment allows people to live at home while attending scheduled appointments.
• Alternative Treatments: Approaches like acupuncture aim to restore bodily balance and have been shown to reduce cravings and withdrawal symptoms. Auricular acupuncture, which involves inserting needles into specific ear points, has been used for substance use disorders since the 1970s.

The Bottom Line

Naltrexone is an effective medication for treating alcohol misuse and reducing cravings. It works by blocking opioid receptors in the brain, preventing alcohol from triggering the release of pleasure chemicals. When combined with behavioral therapies, peer support, and lifestyle changes, naltrexone can help effectively manage alcohol misuse and support the journey toward a healthier life.

If you want to quit drinking but don't know where to start, consider trying Quitemate. This neuroscience-backed app has helped millions of people reduce their alcohol consumption and develop healthier lifestyle habits.