GHB, and it's pro drugs GBL & 1,4-BDO have a dual mode of action, that is, GABA-B agonism and GHB receptor agonism.

The GHB receptor agonism plays a bigger role in GHB's effects, it causes the euphoric, horny, entactogenic stimulation typical of GHB, and it is present even at low doses, since it is what wake u you from G-sleep. It releases dopamine and glutamate, basically the GHB receptor is a stimulant receptor, it's excitatory

Then you got the GABA-B agonism, which actually only manifests itself at higher, more common/medium doses, it is responsible for the sedative and depressant effects. GABA-B agonism actually halts dopamine release, that is why high GHB doses feel dysphoric.

What I'm trying to say, GHB and it's pro-drugs are more stims than depressants, this is the smoothest stimulant I have tried, it makes me write stuff at lightspeed and I'm coherent, there's no scatterbrain stimulation, it treats my ADHD extremely well. Meth, ritalin, cathinones, pyros - they don't even come close to the smooth stimulation this drug induces.

I think this class of drugs should be classified as stimulants and depressants, the stimulant part of GHB has nothing to do with alcohol's btw, completely different MOA.