In news of the truly weird, there is a "disease" that causes people to make puns, compulsively joke, and engage in "wacky" behavior. And you don't want it for more than just social reasons.
Witzelsucht is a mental disorder that causes the sufferer to compulsively make inappropriate jokes or puns — all the time. The condition is generally a result of a stroke in (or an injury to) the orbitofrontal region on the right side of the brain. The frontal lobe is where the personality sits, peering out at the world imperiously. Any changes to this region result in dramatic shifts in mood, tastes, and interests. People who take hits to the left side of the brain often become depressed and angry, while those who are injured in the right side tend to become euphoric and chipper no matter what.
If you're smacking yourself in the right side of the forehead right now, hold off for a second. You will be chipper, but you'll be chipper in a dark room, locked away from everyone because they can't stand you. A 56-year-old man once suffered a stroke in the right orbitofrontal region and developed both witzelsucht and hypersexuality. Of course, the inappropriate joking resulted in him driving off all the women around him. He would joke, make puns, and talk all the time, often to the point where doctors had to interrupt him to conduct tests on him. His jokes would constantly have erotic content, and he didn't care if people told him to stop, or if his wife was around.
A 57-year-old woman suddenly became the life of the party after she suffered a small stroke, but stopped many of her personal hygiene routines. And although people with witzelsucht constantly make jokes, laugh, and sometimes sing all the time, they are unable to respond to the jokes of others. They would sit through jokes or comedic movies completely stonefaced. Try to make new friends that way.
There aren't that many ways to treat the condition. Doctors can try behavioral therapy, like constantly and patiently explaining that puns aren't funny. Ever. When the problem is very bad, however, they can prescribe mood stabilizers to try to return people to their former selves. In some cases, the doctors, out of mercy, might want to prescribe a little something for the patient's caregivers as well.