Opioids
Naltrexone (Vivitrol / Revia)
Street names: Vivitrol, Revia, Depot naltrexone
Overdose? Act now. Call emergency services — say "unresponsive, not breathing". Give naloxone for opioid-like signs. Hotlines
⚡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
Category comparison — Opioids
| Substance | Class | Top risks | Street price |
|---|---|---|---|
| Naltrexone (Vivitrol / Revia) | Not controlled — Rx-only | 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 | ~$1–$3 per tablet |
| Heroin | Schedule I | Extremely addictive — physical dependence in weeks; Overdose: breathing slows or stops | ~$10–$40 per bag |
| Fentanyl | Schedule II | Respiratory depression; Addiction in days | ~$20–$40 per counterfeit pill |
| Fentanyl HCl (powder) | Schedule II / analogue prosecutions | Lab-purity powder is far stronger than street mixes; Weighing errors are fatal | ~$60–$120/gram wholesale equivalent |
| Acetylfentanyl | Schedule I | ~5–15× weaker than fentanyl but still deadly at gram-level mistakes; Frequent cause of cluster overdoses | ~$25–$60/g where found |
| Furanylfentanyl (Fu-F) | Schedule I | Linked to hundreds of fatal overdoses 2016–2018; Potency similar to fentanyl | ~$20–$50/g |
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.