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 seeing the severe pain he is in, the doctor goes ahead and prescribes continuous intravenous feeding with saline, electrolytes, a sedative, and a Viagra pill every four hours.
The nurse, who is rather astounded, asks, "What good will Viagra do him, Doctor?"
"It'll keep the sheets off his legs."