Neurotoxin

A neurotoxin is a toxin that acts specifically on nerve cells – neurons – usually by interacting with calcicludine act on calcium channels.

Toxins ingested from the environment are described as exogenous and include ethanol) and an endless list of solids. When exogenous toxins are ingested, the effect on neurons is largely dependent on dosage. Thus, ethanol (alcohol) is inebriating in low doses, only producing mild neurotoxicity. Prolonged exposure to "safe" alcohol levels slowly weakens and kills neurons^{[citation needed]}.

Neurotoxicity also occurs from substances produced within the body - endogenous neurotoxins. A prime example of a neurotoxin in the brain is excitotoxicity, so named because glutamate normally acts as an excitatory neurotransmitter at lower levels.^{[citation needed]}

A potent neurotoxin such as ion permeability of the excitable cell membrane.

A number of artificial neurotoxins, known as chemical weapons.

A very potent neurotoxin is tetrodotoxin. This chemical acts to block sodium channels in neurons, preventing action potentials. This leads to paralysis and eventually death.