I think he meant toxic specifically as it refers to side effects, making it easier to fool a patient into believing they'd had ibogaine, therefor making a clinical trial more controlled. But ye i think mescaline, despite being safe is reasonable dosages, is more toxic than water in "reasonable doses" ( a glass ig)
That was exactly the thinking. Mescaline and ibogaine appear to produce a similar set of toxic symptoms and have similar durations of action.
Nature published an article on the possible therapeutic use of mescaline for depression, PTSD and related disorders but the metabolism of mescaline in man is still not understood with multiple pathways apparently being responsible given the large number of metabolites detected. It's also important not to presume that the LD50 in one animal will even roughly translate into the LD50 in man. Between species it varies hugely It's also worth considering just what risk is acceptable. If a given dose only kills one in one hundred people, that would be entirely unacceptable for a medicine which (I presume) is why LSD and psilocin have seen far more trials. The TI of both of those drugs is much higher.
Long QT is one of those topics that journalists like to focus on because it sounds so scary.
Psychedelics are powerful psychoactive substances that alter perception and mood processes. Their effectiveness in the treatment of psychiatric diseases was known before their prohibition. An increasing number of recent studies, due to the indisputable ...
www.ncbi.nlm.nih.gov
It's worth noting that the serotonergic anorexic medicines fenfluramine and aminorex were both shown to produce cardiotoxicity but, as in the above examples, that was only found after
chronic exposure. I believe the main reason (which the paper alludes to) is that psychedelics bind to the 5HT2a receptors in the brain but no drug it totally selective and so the drugs will also bind to the 5HT2b receptors of the heart. But they also make clear that simply increasing serotonin levels also has a role.
Their doesn't appear to be any data regarding mescaline's 5HT2a:5HT2b affinity.
It's not as if mescaline is killing lots of people, but if you intend to use a particular compound as a medicine, their needs to be a significant weight of evidence.
It's more appropriate to consider the therapeutic index of a drug rather than the LD50, especially in a drug which displays widely different values between species.