While doing a vasectomy, the doctor slipped and cut off one
of the patient's balls. To avoid a huge malpractice suit, he decided
to replace the missing testicle with an onion.
Several weeks later, the patient returned for a checkup.
"How's your sex life?" the doctor asked.
"Pretty good," the man said, to the doctor's relief.
But then he added, "I've had some strange side effects."
"What's that?" the doctor asked anxiously.
"Well, every time I piss, my eyes water. When my wife gives me
a blow job, she gets heartburn. And every time I pass a hamburger
stand, I get a hard-on."