"Old Viagra" joke

This old man in his eighty's got up and was putting on his coat.

His wife said, "Where are you going?"

"I'm going to the doctor."

"Why? Are you sick?"

"No," he said. "I'm going to get me some of those Viagra pills."

So his wife got up out of her rocker and was putting on her sweater and he said, "Where are you going?"

She said, "I'm going to the doctor too."

"Why?"

"If you're going to start using that rusty old thing again, I'm going to get a tetanus shot."