Intermittent self-catheterization, also called clean intermittent catheterization, is the process of inserting a catheter into the bladder through the urethra for the purpose of draining urine. This process can become necessary when an individual cannot urinate independently. Unlike indwelling catheters, intermittent catheters are inserted as needed and removed when the bladder has been emptied either into a catheter bag or directly into the toilet. While other forms of catheterization remain in place for extended periods of time, intermittent catheterization is prescribed when a patient can either maintain a regular cathing schedule or is able to identify when the urge to urinate strikes.