The toxin is readily absorbed by mucosal membranes, but it does not penetrate intact skin [14] . The bloodstream carries the toxin to the peripheral cholinergic synapses. It enters neurons by endocytosis at the nerve terminal and prevents synaptic vesicles from fusing with the nerve terminal, preventing their release of acetylcholine [81] . As few as 10 molecules of botulinum toxin can irreversibly stop acetylcholine release. The result is complete failure of neuromuscular junction transmission, followed by degeneration of the motor end plate and denervation of the muscle fiber.