Definition of patent medicine
:a nonprescription medicinal preparation that is typically protected by a trademark and whose contents are incompletely disclosed;
also
:any drug that is a proprietary
Note:
Patent medicine is often used to refer to a product (such as an elixir, tonic, or liniment) that was marketed as a medicine in the U.S. during the 1800s and early 1900s but was typically of unproven effectiveness and questionable safety.
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