Though you try many medicines that claim to cure your cold, none of them work. They turn out to be nostrums, or ineffective drugs.
Nostrum refers to a cure-all, a drug, or a medicine that is ineffectual. Before drugs were regulated by the government, there were many nostrums sold to the public. “Snake oil” is one of the most well-known. Said to cure any ailment from achy joints to hair loss, snake oil concoctions could contain a number of ingredients — including camphor, red pepper, and turpentine.