A guy falls asleep on the beach for several hours and gets a horrible sunburn. He goes to the hospital, and is promptly admitted after being diagnosed with second-degree burns. With his skin already starting to blister, and the severe pain he was in, the doctor prescribes continuous intravenous feeding with saline, electrolytes, a sedative, and a Viagra pill every four hours.
The nurse, who is rather astounded, says, "What good will Viagra do for him, Doctor?
The doctor replied, "It'll keep the sheets off his legs."