Chewable calcium carbonate antacid pills - especially Gaviscon! Instead of relieving my heartburn and acid reflux, they fill my esophagus and digestive tract with a putrid, foaming mass that makes me puke. Oh, well... the source of trouble is then gone, at least.
The prescription pain medication after having surgery to remove impacted wisdom teeth, since it would start dissolving the moment I put one in my mouth.
and there was a "protein bar", I don't remember the name, but the HQ is in Park City Ut. It was so foul, that I sent a letter to the office with proof of purchase to get a refund. No response.
I will give the work-safe answer of stewed cardoon; a vegetable related to the globe artichoke. I had read about them in Victorian kitchen gardening guides, and stumbled upon them at the Whole Foods market. I used a recipe out of a victorian cookbook, and braised it in seasoned red wine. The result was absolutely unpalatable. Second place would have to be a Hostess Snowball--lurid pink marshmallow frosting rolled in coconut presumably around some form of cake. Spat it out immediately.
The other day I popped what I thought was a pistachio in my mouth and it turned out to be a pine tree seed, I think. It was horrible! Valerian root tincture is pretty damn disgusting as well.
That little vial of sh*t they make you drink the night before a colonoscopy. Pleasant lemon flavor my a**! By comparison, the colonoscopy wasn't so bad.
No fair! They made me ingest about a gallon of "VILE." The only way I can describe it was diluted laundry detergent (they didn't even attempt to pleasantly flavor this rocket fuel). And the name of stuff: GoLYTELY® ... obviously named by some sarcastic, sadistic pseudo-scientist! (LOL!)
How about that horehound candy they give you at Brigham Young's house? When you leave the house and spit it out, you see the vile candy drops all over the grounds.
Stomake medicine. It's kind of powderd and the bit at the bottom thats mostly powder just makes me puke. Then beans. It kind of explodes into some almot powdery stuff again and I want to be sick.