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Opioids

Naltrexone (Vivitrol / Revia)

Street names: Vivitrol, Revia, Depot naltrexone

Naltrexone (Vivitrol / Revia) — 50 mg tablets; 380 mg monthly injection (Vivitrol)

What it does

  • Full opioid BLOCKER — prevents any opioid high for 24 h (tablet) to a month (injection)
  • Also reduces alcohol reward (Sinclair method)

Key risks

  • PRECIPITATED WITHDRAWAL if taken while opioids are in the system — must be fully detoxed first (7–10+ days)
  • Blocks pain relief from opioids in emergencies — carry the Vivitrol card
  • Overdose risk paradox: tolerance drops during blocking; using through the block escalates doses dangerously
  • Hepatotoxicity at high doses (historic concern, rare at therapeutic)

Overdose signs

  • (Rare alone) nausea, headache; the danger is the post-treatment relapse overdose

📋Quick facts

Also known asVivitrol, Revia, Depot naltrexone
CategoryOpioids
Schedule / classNot controlled — Rx-only
Appearance50 mg tablets; 380 mg monthly injection (Vivitrol)
Street price~$1–$3 per tablet; injection $1,000+ (insurance covers in US)
Legal statusRx-only everywhere; standard medication for opioid and alcohol use disorder
Last updated2026-09-18
Sources: FDA, EMA, SAMHSA

Category comparison — Opioids

SubstanceClassTop risksStreet price
Naltrexone (Vivitrol / Revia)Not controlled — Rx-onlyPRECIPITATED WITHDRAWAL if taken while opioids are in the system — must be fully detoxed first (7–10+ days); Blocks pain relief from opioids in emergencies — carry the Vivitrol card~$1–$3 per tablet
Suboxone (buprenorphine/naloxone)Schedule IIIDependence (milder than full opioids); Precipitates withdrawal if taken too soon after other opioids~$10–$25 per 8 mg film
Naloxone (Narcan)Not controlled — OTCShort half-life (30–90 min) vs fentanyl's hours — the person CAN RE-OVERDOSE as it wears off. Stay and repeat; Precipitates withdrawal in dependent users — expect anger, vomiting, pain (they're alive — that's the point)US OTC ~$45
MethadoneSchedule IIAccumulates over days — overdose risk highest in first 2 weeks; Fatal mixing with benzos/alcohol~$10–$40 per 40 mg diskette
Street prices are regional estimates. Potency and cuts vary constantly.

?Frequently asked questions

What does Naltrexone (Vivitrol / Revia) look like?

50 mg tablets; 380 mg monthly injection (Vivitrol)

What are the signs of a Naltrexone (Vivitrol / Revia) overdose?

(Rare alone) nausea, headache; the danger is the post-treatment relapse overdose Call emergency services immediately and give naloxone if available — it reverses opioid overdoses.

How addictive is it?

PRECIPITATED WITHDRAWAL if taken while opioids are in the system — must be fully detoxed first (7–10+ days) Dependence can develop with regular use.

🔗Sources & further reading

Facts on this page are compiled from these primary sources. External links open in a new tab.