A urine tube extends through a balloon which is inflatable in the neck of a bladder to form a seal around the urine tube. The balloon has a shape corresponding to the shape of the bladder chamber at the urethra orifice to facilitate establishing a seal. A valve is provided on the outlet end of the urine tube and an air tube extends along the substantial length of the urine tube into the balloon. A hypodermic syringe or the like may be inserted into the inlet end of the air tube for inflating the balloon. A hydrogel collar is positioned around the urine tube against the body at the outlet end of the urethra to hold the balloon in tight engagement with the bladder neck at the urethra orifice.