The global medication scheduling is changing due to the frequent launching of new and generic medicines which bringing about the accessibility of different kind of medic ines for customers in pharmacies. The Over the Counter medicines market is always under investigation due to its nature of self medication . In this study, the major psychological factors like attitude, subjective norm, perceived behavioral control and perceived risk are considered in consumers as the determinant of the over the counter medicine purchase decision. This study incorporates the extended theory of TPB t o effectively measure the research constructs . A non probabilistic purposive sampling technique has been applied to choose 308 respondents from the metropolitan territory of Kuala Lumpur and Selangor stat es in Malaysia. The E xploratory F actor A nalysis and Structural Equation M odelling technique have been used to analyse the data. The results revealed that customers attitude, subjective norm and perceived behavioral control towards OTC medicine wer e of ver y supportive significance whereas perceived risk w as not significant. It would be fascinating to explore if the results based on the outcomes hold for populaces of other ASEAN nations as the re are different social settings, national approach, and healthcare guidelines. Thus, OTC

medicine usage and purchase behaviour could be an integrative part of global healthcare frameworks and priorities.

Keywords: Over the Counter Medicine, Consumer Behaviour, TPB, Malaysia