Neuromuscular junction toxins.

The neuromuscular junction (NMJ) is highly susceptible to neurotoxins due to its lack of protective barriers like the blood-brain barrier. Over time, a wide range of natural toxins have evolved to target the NMJ, derived from animals, plants, and bacteria, alongside modern synthetic compounds developed for use in medicine, insecticides, and warfare. These toxins exert their effects through various mechanisms, such as antagonizing or agonizing nicotinic and muscarinic acetylcholine receptors, or inhibiting neurotransmitter release or breakdown. Despite their diverse origins and actions, NMJ toxins often present clinically with muscle weakness and can lead to respiratory failure if untreated. However, variations in presentation and clinical context are critical for accurate diagnosis and appropriate treatment. Understanding these mechanisms is essential for early recognition, effective management, informed use of current medications, and the development of novel therapeutics.