A portacath is an implanted venous access device for patients who need frequent or continuous administration of chemotherapy. Drugs used for chemotherapy are often toxic, and can damage skin, muscle tissue, and sometimes veins. They often need to be delivered into large central vein where the drugs are immediately diluted by blood stream and delivered efficiently to the entire body. Cancer patients also require frequent blood tests to monitor their treatments. For patient with difficult veins, it can be used for withdrawing blood for blood tests.