Britannica Sources used in this answer

How do diphtheria and botulism toxins attack the nervous system?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

epilepsy — nervous system disease Epilepsy monitoring during a neurological evaluation.

Diphtheria and botulism toxins attack the nervous system through distinct pathological mechanisms:

Botulism: The botulinum toxin targets the autonomic nervous system by blocking the release of acetylcholine, a neurotransmitter essential for muscle contraction. Once the toxin reaches nerve endings in muscles, it prevents nerve impulses from passing to the muscle fibers, resulting in flaccid paralysis.12
Diphtheria: The diphtheria toxin causes damage to the nervous system by inducing a severe loss of myelin from motor nerves. This demyelination leads to weakness and paralysis, which often manifests in the throat and other muscles, sometimes appearing weeks after the initial infection seems to have resolved.34

While both conditions result in paralysis, botulism acts by inhibiting chemical signaling at the neuromuscular junction, whereas diphtheria toxin causes structural damage to the nerve fibers themselves.132