I've been drinking and bathing with (massaging into the skin) my own urine for over a year now.
It's noticeable that bathing has a different effect than drinking. I imagine it's similar to injecting in that it bypasses the digestive tract and is absorbed through the skin, into the tissue and blood vessels directly beneath.
When I don't bathe (as well as drink) I feel less energetic and weaker with less endurance. I'm intuiting that it's more benign, natural and less invasive than injections; plus it keeps the skin hydrated and soft due to the uric acid, naturally occurring oils and literally thousands of ingredients that also nourish the skin.