3 ms·

> see for example the recent study showing no difference to placebo for ketamine under anaesthetic That's not counterevidence to ketamine's efficacy, it's evid

> see for example the recent study showing no difference to placebo for ketamine under anaesthetic That's not counterevidence to ketamine's efficacy, it's evidence that the efficacy, if prior studies soundly demonstrated it, relies somehow on the user not being anesthetized during the treatment. I don't think that surprises many advocates of psychodelic or hallucinogenic therapies. And these are not the first class of treatments where blinding isn't practical. It does confound some forms of analysis when you can't acheive real blinding, but we've devised many alternative forms of analysis that we take as scientifically "good enough" to treat something as medicine.

WhitneyLand 3y ago
Ketamine is an anesthetic. Seems like the study raises serious questions about efficacy.
- sterlind 3y ago
  Ketamine is a dissociative that's used as an anesthetic. General anesthesia is a different beast. The precise mechanism GAs use isn't understood, but they cause slow waves of electrical activity to wash over the brain, constantly resetting neural networks and preventing communication, leading to coma. This includes breathing, which is why the patient needs to be intubated. Ketamine doesn't stop respiration. It causes profound dissociation and hallucinations, but I don't think it causes coma. It's definitely doing different things than GAs, at least. So it doesn't seem unreasonable that ketamine wouldn't work if you're in a coma. I'd be surprised if LSD did either. Or anything, for that matter. There's not a lot metabolically happening in a neuron under coma.
  - pas 3y ago
    Propofol works even on Venus flytrap plants. That's how deep this particular 'off' switch seems to be wired in. (It's blocking the presynaptic sodium and calcium channels.)
  - LoganDark 3y ago
    I think in other words, stuff like ketamine and LSD don't perform magic all on their own. You have to be consciously experiencing it in order for them to have any effect on you.

WhitneyLand 3y ago

Ketamine is an anesthetic. Seems like the study raises serious questions about efficacy.

sterlind 3y ago
Ketamine is a dissociative that's used as an anesthetic. General anesthesia is a different beast. The precise mechanism GAs use isn't understood, but they cause slow waves of electrical activity to wash over the brain, constantly resetting neural networks and preventing communication, leading to coma. This includes breathing, which is why the patient needs to be intubated. Ketamine doesn't stop respiration. It causes profound dissociation and hallucinations, but I don't think it causes coma. It's definitely doing different things than GAs, at least. So it doesn't seem unreasonable that ketamine wouldn't work if you're in a coma. I'd be surprised if LSD did either. Or anything, for that matter. There's not a lot metabolically happening in a neuron under coma.
- pas 3y ago
  Propofol works even on Venus flytrap plants. That's how deep this particular 'off' switch seems to be wired in. (It's blocking the presynaptic sodium and calcium channels.)
- LoganDark 3y ago
  I think in other words, stuff like ketamine and LSD don't perform magic all on their own. You have to be consciously experiencing it in order for them to have any effect on you.