Opioid Antagonists
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Overview
Opioid antagonists block opioid receptors in the brain and body. They are used to treat opioid use disorder (OUD) and alcohol use disorder (AUD) by eliminating the euphoric and sedative effects of opioids or reducing alcohol cravings.
How do opioid antagonists work?
Opioid antagonists competitively bind to mu (μ), kappa (κ), and delta (δ) opioid receptors without activating them. By occupying these receptors, they block the effects of exogenous opioids (preventing euphoria) and, in the case of alcohol dependence, modulate the endogenous opioid system to reduce the rewarding effects of alcohol and decrease cravings.
Drugs in this class
- Naltrexone (Vivitrol, ReVia)