That one is required by law.
Do not taunt Happy Fun Ball.
One of the things they specifically tell you in pregnancy class is that once the mother’s water has broken and she is at the hospital in active labor, the two of you are to avoid intercourse. Jeff Foxworthy mentions this in one of his routines, noting that they wouldn’t tell you not to do it unless some people did it. “So, uh … just how far apart are the contractions there, sweet thing? Seems like a shame to waste this semi-private room.”
Especially for the asthma drug - that may include death from asthma.
Mandatory Jeff Foxworthy quote:
Jeff Foxworthy: I remember when I was a kid, there were two medicines: aspirin and Campho-Phenique, that was it. But they advertise these prescriptions, and half the time, the side effects are 50 times worse than what the thing cures! It’s like, “Try new Flor-A-Flor. For itchy, watery eyes, it’s Flor-A-Flor. Side effects may include: nausea, vomiting, water weight gain, lower back pain, receding hairline, eczema, seborrhea, psoriasis, itchy chafing clothing, liver spots, blood clots, ringworm, excessive body odor, uneven tire wear, pyorrhea, gonorrhea, diarrhea, halitosis, scoliosis, loss of bladder control, hammertoes, the shanks, low sperm count, warped floors, cluttered drawers, hunchback, heart attack, low resale value on your home, feline leukemia, athlete’s foot, head lice, club foot, MS, MD, VD, fleas, anxiety, sleeplessness, drowsiness, poor gas mileage, tooth decay, split ends, parvo, warts, unibrow, lazy eye, fruit flies, chest pains, clogged drains, hemorrhoids, dry heaving, and sexual dysfunction.” I’m like, “I’ll just have itchy, watery eyes!”
My favorite “dramatization” disclaimer was for some dishwasher detergent that showed tiny men with construction equipment scraping the dried food off of the dishes in the dishwasher. Really? That’s not what happens in there?
Dave Barry once wrote about these pharmaceutical ads and how they all have two very conflicting messages. One, you really need to be taking this drug. And two, this drug will probably kill you. 
The old con game was that a campaign would run a hugely negative ad against the opposition and then the candidate would step forward and say *"I am completely shocked by this ad which states that my opponent Congressman Bob Smith molested children. It was never my intent to say that Congressman Bob Smith molested children or to imply in any way that Congressman Bob Smith molested children. And I certainly would never have authorized these ads that told people Congressman Bob Smith molested children.
My staff has conducted a thorough investigation into the Congressman Bob Smith molesting children issue to determine how these ads saying Congressman Bob Smith molested children were released. We found that these ads, which allow me to repeat one more time said Congressman Bob Smith molested children, were the work of a single unpaid volunteer who joined our campaign three days ago.
Naturally we deeply regret that this volunteer told people that Congressman Bob Smith molested children (okay, one more time) and have fired him. So there will be no more ads telling people that Congressman Bob Smith molested children (last time really)."*
The basic purpose of the law was to force candidates to acknowledge that they knew what their ads were saying and take responsibility for them.
Maybe we should start requiring pharmaceutical-style disclaimers for political ads:
I once saw a charcoal grill in a store with the warning “Watch children and pets while burning.”
The disclaimers exist because even frivolous lawsuits take time and money to defend against. In a society as litigious as ours, it’s better for business to disclaim too many times than not enough.
Way to be a buzzkill.
“This medicine is sure to put a stop to your symptoms…And your life.”
Did it have this NFPA label on it?
I burning your dog!
Not really in the spirit of the OP but I always got a kick out of the neighborhood street signs that said: “Slow children at play”. There was no division between “slow” and “children”, so it read as though it was saying there were a bunch of mentally challenged children out and about in the 'hood.
Or are not fast enough to get out of the way of a car.
My favorite: May cause an irresistible urge to gamble…
Well that’s not very funny.
“But I repeat myself.”
Side effects include Restless Pants Syndrome, Chris Hanson’s Disease, and DVDiptheria.