Abstract: An improved catheter for the dispensing of pharmaceutical fluids, such as insulin, has a cannula with not only a conventional end opening, but also a plurality of micro perforations in the cannula wall, which prevent flow blockages of pharmaceutical fluids if the cannula becomes kinked near its open end. The perforations are located in a portion of the cannula wall that is intended to be installed beneath the patient's skin. Thus, if the end opening becomes blocked because of a kink in the cannula near the open end, the pharmaceutical fluid can still enter the patients blood stream through the micro perforations in the cannula wall. Perforations are preferably formed in a spiral pattern along a portion of the cannula to prevent diametrically opposed perforations that might compromise cannula wall strength.