Opioids (heroin, morphine, fentanyl, tilidine, tramadol) act on μ-opioid receptors and reduce respiratory drive. GHB/GBL acts GABAergically on the respiratory center. In combination, the respiratory depression is doubly unpredictable.
Clinically documented consequences:
- Respiratory depression even at moderate dosing
- Naloxone reverses only the opioid portion — GHB sedation remains
- Delayed complications, because GHB breaks through again after the naloxone wears off
If opioid involvement is suspected: naloxone nasal spray (Nyxoid, OTC since 2024). But: don’t leave the person alone, even after naloxone has worked. Monitor breathing for hours.
In the chemsex context and in polydrug use, this combination is one of the most common causes of death — even in people who otherwise have well-established use habits.
We recommend avoiding this combination.