A catheter with a retractable anchor mechanism for providing drugs and/or electrical stimulation to the human body. The catheter has a flexible tubular casing consisting of a outer member and an inner member which enclose at least one lumen. The retractable anchor mechanism is located near the distal end of the catheter and is moveable from a first extended position to a second retracted position. A capture member is connected to the anchor mechanism. The capture member has a socket portion and a necked down portion for guiding the enlarged tip of a stylet into the socket portion for releasable engagement therewith. The anchor mechanism is moved from the first extended position to the second retracted position by inserting a stylet and applying pressure in the distal direction and is moved from the second retracted position to the first extended position by partially withdrawing the stylet thereby applying pressure in the proximal direction. The anchor mechanism consists of a plurality of lobes in one embodiment and of a continuous diaphragm in another.