GHB/GBL and ketamine in a chemsex context are a well-known combination, but clinically problematic. GHB acts as a GABAergic depressant and suppresses breathing, while ketamine acts dissociatively and reduces the swallowing reflex.
Clinical consequences:
- A K-hole can become life-threatening if the person is lying unable to move while the GHB breathing becomes shallow at the same time
- Aspiration risk from vomiting without an intact swallowing reflex
- Hard to assess for bystanders whether someone is “just in a K-hole” or acutely critical when it comes to breathing
- Rebound complications after GHB wears off can worsen the ketamine hangover
In a chemsex setting, mephedrone or methamphetamine is often added on top — the combined toxicity then becomes even more unpredictable.
We recommend avoiding this combination. If you are experienced with chemsex and still want to combine: keep them apart (hours of spacing), have an awareness person who has not used any substances, never alone, never in water/pool/sauna.
Points of contact: Schwulenberatung Berlin (chemsex counseling), Deutsche Aidshilfe.