In current business environment, main goal of pharmaceutical companies, apart from making quality product/service is fulfillment of costumers needs which are more demanding and complex nowadays. Analyse of consumers behaviour as a specific part of marketing started when The manufacturers realised that consumers don’t always act and react with the perception of marketing theory. Analysing consumers behaviour is focusing on how one person decides to invest their available resources (time, money, effort) in factors connected to consuming. Pharmaceutical companies must continually analyse behaviour of their consumers in addition to satisfy their needs and to ensure increase of product sales and making profit. Only content consumer can become a loyal buyer of specific pharmaceutical company. In competitive economical system, company’s growth demands precise knowledge of their consumers: how, why and where do they shop and what exactly do they buy. Main purpose of marketing is not about finding costumers or encouraging people to buy whatever that particular company produces. Today management success depends more than ever on combining well all the aspects - product, advertisement, postselling services and furthermore – until fulfillment of customer’s demands, which is exactly the main purpose of devotion to customer. In this thesis, the focus will be placed on factors which influence consumers behaviour on market of over-the-counter medicines. Intention of this particular thesis is to research how specific inside and outside factors influence on consumers behaviour on over-the-counter drugs market and how the marketing is created for this specific industry.