A method and a device for forming holes (17a, 17b) through a lateral wall of a catheter are disclosed. The method comprises the steps of providing a section of the catheter between a pair of tubular punching members 6, driving at least one of said pair of tubular punching members towards the other in order to punch through said lateral wall 23 of the catheter and thereby sever one pair of oppositely located hole pieces from the lateral wall, actuating an ejection unit 7, in order to force said severed hole pieces away from the catheter via said internal lumen of the tubular punching members, withdrawing said pair of tubular punching members. A catheter 2 produced is also disclosed.