Envenomations resulting from stings of the scorpion Androctonus australis are responsible for many cases of death and morbidity in North Africa. The high toxicity of the venom is primarly due to three polypeptide neurotoxins, designated AahI, AahII and AahIII. These toxins act on sodium channels of excitable cells. While AahI and AahIII belong to one group, AahII belongs to the other group by classification of immunology and structure.