What Does Vivitrol Do?

What does Vivitrol do for people recovering from addiction? Studies show that those who used Vivitrol with rehabilitation and continuing therapy were 17 times less likely to relapse compared to those who did not use the medication. People who combined Vivitrol with counseling to treat alcohol use disorder experienced a 25 percent greater reduction in heavy drinking days after completing treatment. Vivitrol is a long-acting injectable form of naltrexone that the FDA approved in 2006. What is Vivitrol used for? This medication treats both alcohol use disorder and opioid use disorder by blocking the euphoric effects of these substances. This piece will explain how Vivitrol works and its uses in addiction treatment. You will also learn about potential risks and critical safety precautions you need to know.

What Is Vivitrol and How Does It Work

Vivitrol represents an extended-release injectable formulation of naltrexone that addresses a core challenge in addiction recovery: medication adherence. Unlike daily oral tablets that patients must remember to take, you receive one intramuscular injection every four weeks.

Vivitrol as an Extended-Release Injectable Form of Naltrexone

The FDA approved extended-release injectable naltrexone in 2010 to prevent relapse to opioid dependence following detoxification. Each injection delivers 380mg of naltrexone embedded in biodegradable microspheres. A healthcare provider administers the shot deep into your gluteal muscle and alternates between buttocks for subsequent injections.

The microsphere technology controls how naltrexone releases into your body. After injection, the microspheres begin absorbing water and swelling, which triggers a release of the medication. Your plasma concentration peaks approximately 2 hours after injection, followed by a second peak 2 to 3 days later. Around 7 days after dosing, concentrations decline while maintaining therapeutic levels for over a month. The polymer matrix breaks down into lactic acid and glycolic acid, which your body metabolizes and eliminates as carbon dioxide and water.

How Naltrexone Blocks Opioid Receptors in the Brain

Naltrexone functions as a competitive antagonist at opioid receptors in your brain. It binds with highest affinity to the mu opioid receptor while also acting as a weaker antagonist at kappa and delta opioid receptors. Naltrexone blocks the euphoric and sedative effects of opioids such as heroin, morphine, and codeine by occupying these receptors.

The mechanism operates differently for alcohol use disorder. Alcohol stimulates the release of endogenous opioid neurotransmitters, endorphins and enkephalins, that bind to opiate receptors in your brain. Naltrexone binds to these endorphin receptors and blocks the effects and feelings that alcohol produces. This action makes alcohol ingestion less pleasurable because it prevents the rewarding effects associated with drinking.

The Role of Vivitrol in Reducing Cravings

Naltrexone binds and blocks opioid receptors while reducing and suppressing opioid cravings. Research demonstrates that naltrexone decreases reactivity to drug-conditioned cues and decreases craving. The medication has no abuse or diversion potential beyond blocking the pleasure from substances. You must combine Vivitrol with counseling and psychosocial support for the treatment to work.

What Is Vivitrol Used For in Addiction Treatment

The FDA granted approval for Vivitrol to treat two distinct conditions at different times. The agency approved extended-release naltrexone for alcohol dependence treatment in 2006. Four years later, the FDA approved the medication to prevent relapse in opioid dependence in 2010.

Treating Alcohol Use Disorder with Vivitrol

Vivitrol blocks endorphins from binding to their receptors and ends the pleasurable feeling associated with drinking. This is different from older medications like disulfiram, which discourage drinking by causing illness if you consume alcohol. You must abstain from alcohol for at least 7 to 10 days before starting treatment.

Clinical trials demonstrate measurable benefits. People who used Vivitrol with counseling experienced a 25 percent greater reduction in heavy drinking days compared to those receiving counseling alone. Heavy drinking days are defined as five or more drinks daily for men and four or more for women. Patients whose alcohol use disorder was treated with both Vivitrol and rehabilitation counseling spent more time abstinent. They also had lower relapse rates.

Preventing Relapse in Opioid Use Disorder

Vivitrol attaches to opioid receptors and prevents other opioids from interacting with them for opioid dependence. People who combined Vivitrol with counseling achieved 90 percent opioid-free weeks compared to 35 percent who took a placebo. Studies on criminal justice offenders showed that extended-release naltrexone reduced relapse risk by half compared to treatment as usual.

Why Vivitrol Must Be Combined with Counseling and Therapy

Vivitrol is medication-assisted treatment that requires concurrent counseling to work. Clinical studies indicate that Vivitrol combined with counseling and behavioral therapy has shown a 90 percent success rate in helping people maintain sobriety. The medication addresses physical cravings. Therapy tackles the root issues, develops coping skills and modifies behaviors associated with substance use. There is no standalone prescription cure for addiction.

Common and Serious Side Effects of Vivitrol

Most people experience mild side effects during Vivitrol treatment, though serious reactions can occur. You can monitor your health better when you understand these risks.

Nausea, Headache, and Other Common Side Effects

Common side effects differ between treatment types. Treatment for alcohol use disorder may bring muscle cramps, dizziness, nausea and vomiting, or injection site reactions. Opioid use disorder treatment shows different patterns: elevated liver enzymes, common cold symptoms like runny or stuffy nose, insomnia, and toothache appear more often.

Other mild side effects include belly pain, decreased appetite, diarrhea, sleepiness, fatigue, joint pain or stiffness, and headache. These symptoms are temporary and may resolve as your body adjusts to the medication.

Injection Site Reactions and Tissue Damage

Most injection site reactions cause mild pain, tenderness, bruising, redness, or swelling. Severe complications can develop though. One patient in clinical trials developed enlarging induration after 4 weeks that led to necrotic tissue and required surgical excision. Postmarketing reports documented additional cases with cellulitis, hematoma, abscess, sterile abscess, and necrosis. Some cases resulted in substantial scarring and required surgical debridement. Nearly 196 reports of injection site reactions have been documented. Sixteen patients required surgical intervention.

Liver Damage and Hepatitis Symptoms

Cases of hepatitis and substantial liver dysfunction have occurred during Vivitrol treatment. Symptoms include belly pain that persists, unusual tiredness, dark or cola-like urine, and jaundice. Elevated liver enzyme levels above three times the upper limit occur in about 1% of patients. People with alcohol-related liver disease, hepatitis B or C, or those taking other hepatotoxic medications face higher risk.

Risk of Opioid Overdose After Treatment

Your opioid tolerance decreases during Vivitrol treatment. Twenty-two of 52 fatal overdoses reported occurred within two months of the last injection. Patients on Vivitrol are more than twice as likely to overdose compared to those on buprenorphine. You become vulnerable to overdose at the end of dosing intervals, after missing doses, or after treatment discontinuation.

Important Safety Precautions Before Starting Vivitrol

You must follow strict safety protocols before starting Vivitrol to protect yourself from complications.

Must Be Opioid-Free for 7-14 Days Before First Injection

All opioid use must stop for at least 7 to 14 days before you receive your first Vivitrol injection. This has street drugs and prescription pain medicines, plus cough, cold, or diarrhea medicines that contain opioids. Opioid dependence treatments like buprenorphine or methadone also require discontinuation. Opioids used within this timeframe can trigger withdrawal symptoms severe enough to require hospitalization.

Naloxone Challenge Test to Confirm No Opioid Dependence

Your healthcare provider may administer a naloxone challenge test to verify you are opioid-free. This test involves a small dose of naloxone injected to check for physical dependence. Withdrawal symptoms that appear during the test mean you cannot start Vivitrol at that time. The provider may repeat the test after more opioid-free days.

Alert Family Members About Overdose Risks

Family members and close contacts must know about your increased sensitivity to opioids and overdose risk. Your healthcare provider should discuss naloxone or nalmefene availability for emergency overdose reversal.

Carry Medical Identification While on Vivitrol

Carry written information that identifies your Vivitrol treatment status so emergency responders can treat you properly. Medical identification cards, bracelets, or necklaces ensure healthcare providers know you are taking naltrexone, especially if opioid-based pain relief becomes medically needed.

Conclusion

Vivitrol offers a powerful medication-assisted treatment option when you combine it with counseling and behavioral therapy. The monthly injection blocks opioid receptors and substantially improves success rates for both alcohol and opioid use disorder. Strict adherence to safety protocols matters most, especially when you have to maintain the required opioid-free period before treatment. You should work with your healthcare provider to monitor potential side effects and ensure this treatment approach lines up with your recovery goals.