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Scorpion venoms are very toxic with very fast diffusion and action, explaining the observed early symptoms in envenomed patients. Biochemical analysis of scorpion venoms showed a complex composition with toxic and nontoxic fractions. The nontoxic fraction is a mixture of mucopolysaccharides, enzymes (e.g., hyaluronidases and phospholipases), protease inhibitors, and bioamines such as serotonin and histamine. Toxic fraction is the best studied; it consists mainly in highly specific neurotoxins to ion channels of excitable cells. Although having high sequence identity (sodium, potassium, calcium, or chloride) these neurotoxins differ in their degree of toxicity and affinity to specific target of animal species (mammals, crustaceans, and insects), there are also toxins with dual specificity (anti-mammal and anti-insect). High similarity of toxic effects and, antigenic structures of neurotoxins exist between scorpion species. Venom composition depends on the species and their geographic originsm. Toxic manifestations observed after exposure to scorpion venom are due to its neurotoxins which act on sodium or potassium channels of nerve endings, leading to neurotransmitter release that can induce general symptoms resulting in local pain, inflammation, cardiorespiratory distresses, and neurological disorders.