The present invention relates to a balloon (1) for treating stenosis and the method for obtaining this balloon. The method comprises the steps of: bringing the balloon in the deployed configuration placing a plurality of stylets (17) that are arranged in the axial direction along the outer wall (10) of the balloon pushing the stylets towards the balloon core (11) in the radial direction such as to form a plurality of laps (12) laying the laps about the core in the tangential direction such as to lay each lap on an adjacent stylet removing the stylets such as to form a plurality of cavities (13) comprised between each lap and the balloon core filling the cavities with the drug.