Well Head & Shoulders shampoo sure the fuck is. They sell it as anti-dandruff, but in all their advertising they demonstrate dry scalp not dandruff. Dry scalp creates tiny flakes, ahd Head & Shoulders shampoo is very drying, so it CAUSES the thing they pretend to be curing. In fact it does cure dandruff, it's just that people don't know what dandruff is, so they legally get away with it.

Similar story with mint-flavored antacid tablets. They cause acid reflux via the mint. Mint relaxes the muscle that holds your stomach closed.