Objectives The objective of this paper is to give insights into the latest knowledge about pharmacological characteristics of botulinum toxin type A (BoNT-A) and give a brief historical overview of the discovery the toxin molecule until the first application of the drug in clinical practice. The currently registered BoNT-A preparations in the global market, their similarities and differences in terms of formulation, indications and other characteristics relevant to clinical application will be described in particular. Material and methods For the needs of this paper relevant scientific and professional literature, scientific publications, medicine database of the Agency for Medicinal Products and Medical Products of the Republic of Croatia, the web pages of the European Medicines Agency, and the American Food and Drug Agency were searched. Bibliographic databases are searched by keywords: botulinum toxin type A, Botox, Dysport, Xeomin, indications, mechanism of action, side-effects, dosing, clinical effect, clinical trials, disease. Results Clostridium botulinum is a genus of sporulating and anaerobic Gram-positive, rod-shaped bacteria with unique properties of botulinum neurotoxin production of which 7 subtypes (AG) are now described. The biologically active part of the BoNT type A molecule comprises a polycompetent chain of ~ 150 kDa consisting of a light chain (L chain, 50 kDa) and a heavy chain (H chain, 100 kDa). L and H chain are held together by a long peptide belt and one disulfide bond . Two subdomains of the H chain provide specific binding to the nerve endings and endocytosis of the neurotoxin, whereby due to the acidic pH in the endosome disulfide linkage and the short chain toxin translocation into the cytosol occur. L chain is a Zn2+ dependent protease that specifically cleaves SNAP-25, one of the key proteins for the process of secrete neurotransmitters from the nerve endings. High selectivity for cholinergic neurons leads to inhibition of the secretion of acetylcholine and muscle paralysis, and dysfunction of autonomic synapses, symptoms typical of botulism. However, the picogram amounts of BoNT-A injected directly into the muscle or dermis are therapeutically used in various conditions characterized by muscular hypercontractility and autonomic disorders. So far, there are three registered BoNT-A preparations in the EU market: Botox®, Dysport® and Xeomin®. In this paper, their differences are compared, from the production process, the difference in doses, to the approved indications. Conclusion The basis of the pharmacological action of BoNT-A is the inhibition of neurotransmitter secretion from the peripheral cholinergic, but also the sensory endings. BoNT-A is potent and neurospecific, has a limited degree of diffusion after local application, and its action is reversible. Despite certain deficiencies in understanding the mechanism of action and the pharmacokinetic properties of the toxins in the body, BoNT-A preparations are widely used in various indications, and the administration is characterized by long acting after single use and good tolerance. The use of BoNT-A has so far been approved in 11 indications, while offlabel is applied in more than 20 indications.