Sorry, that's wrong, at least as far as caffeine is concerned, and certainly as far as adverse behavioural effects ("behavioural toxicity") are concerned in humans.

https://www.sciencedirect.com/science/article/pii/S131901642...

Oh, interesting, thanks. I'm not sure why you're downvoted. What about nicotine?

No idea on that front. The caffeine one struck a chord because I'm a slow metaboliser, and it can cause me issues with anxiety under the wrong circumstances. It does make me wonder how many cases of anxiety are at least exacerbated by genetic issues with processing caffeine and other stimulants.

Curse you science! Still, this is just in rats. Rats with their weak rat brains. My superior human brain can easily absorb this caffeine with no ill effects!

That Kang et al. study was 50mg/kg of caffeine administered three times a day. That would be about a hundred cups a day of coffee for my body weight. Don't they say the dose makes the poison?

Opiates are not neurotoxic.

There are many reports of opiate neurotoxicity https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1949075/

https://www.pharmacistsmb.ca/files/2001/May-June/Opioid_Indu...

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9007125/

Neurotoxic in the sense of having adverse events of a neurological nature.

Neurotoxic does not mean “your neurons are damaged”, at least not how those articles define it.

So there are two totally different definitions of neurotoxic used in the medical field?

No, the scientific field uses it differently than the layman.

Neurotoxic to a scientist means “can have negative impact to brain function, whether temporary or permanent”.

The layman thinks neurotoxic means “kills your brain cells”.

What makes you think any of us were using the lay definition?

Because if someone said “opioids are neurotoxic” from a scientific definition, it’s stating the obvious.

Both definitions are correct.

From Wikipedia:

> Neurotoxicity is a form of toxicity in which a biological, chemical, or physical agent produces an adverse effect on the structure or function of the central and/or peripheral nervous system. It occurs when exposure to a substance – specifically, a neurotoxin or neurotoxicant– alters the normal activity of the nervous system in such a way as to cause permanent or reversible damage to nervous tissue.

Brain cells getting killed is a normal process, you could call it pruning. Cells grow back, you know!

Both contain practically the entire family of beta-carbolines, which includes several neurotoxic alkaloids.