Naltrexone ER injection
VIVITROL
What it isA monthly IM mu- and kappa-opioid antagonist; alcohol use disorder and relapse prevention in opioid use disorder.
Why this oneIt removes daily adherence from oral naltrexone and cannot be diverted or misused as an opioid.
What limits itIt requires 7-14 opioid-free days first; injecting sooner can precipitate withdrawal, and the medication blocks opioid analgesia.
FDA-approved for
- alcohol use disorder (2006)
- opioid use disorder (relapse prevention) (2010)
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Alcohol dependence | Adults (able to abstain before initiation) | 380 mg IM q4 weeks | 380 mg IM q4 weeks | 380 mg q4 weeks |
| Prevention of relapse to opioid dependence after detox | Adults (opioid-free ≥7–10 days) | 380 mg IM q4 weeks | 380 mg IM q4 weeks | 380 mg q4 weeks |
Renal Caution in moderate to severe renal impairment; no adjustment for mild
Hepatic No adjustment for mild–moderate; not evaluated in severe
Administer every 4 weeks (monthly)
Instructions
- Deep IM gluteal injection only; prepared and administered by a healthcare provider
- Ensure opioid-free 7–10 days before first dose
- Alternate buttocks with each injection; do not give IV or SC
Contraindications
- Patients receiving opioid analgesics
- Patients with current physiologic opioid dependence
- Patients in acute opioid withdrawal
- Any individual who has failed the naloxone challenge test or has a positive urine screen for opioids
Cautions
- Vulnerability to opioid overdose (reduced tolerance)
- Injection site reactions (some severe, incl. necrosis)
- Precipitation of opioid withdrawal
- Hepatotoxicity
- Depression and suicidality
- Eosinophilic pneumonia
- Hypersensitivity/anaphylaxis
Adverse reactions
- Nausea
- Vomiting
- Injection site reactions
- Muscle cramps
- Dizziness/syncope
- Somnolence/sedation
- Decreased appetite
- Hepatic enzyme abnormalities (opioid dependence)
- Injection site pain
- Nasopharyngitis
- Insomnia
- Toothache
Pregnancy Insufficient human data; animal data show early fetal loss at high exposures
Lactation Naltrexone and 6β-naltrexol present in human milk; no data on breastfed infant
⚠ BOXED WARNINGS
- Addiction, abuse and misuse
- Life-threatening respiratory depression
- Risk from concomitant use with benzodiazepines
Classes and tags
Clinical profile
Mechanism of action: Naltrexone ER injection ballicule
Open Naltrexone ER injection in the interactive console ↗
Memory aids: mascots and interaction avatars
dilated pupils → opioid blocker
