From Longman Dictionary of Contemporary Englishpatent medicinepatent medi‧cine /ˌpeɪtnt ˈmedsən $ ˌpætnt ˈmedəsən/ noun [countable] MDBBTa medicine which can be bought without a prescription (=a written order from your doctor) SYN over-the-counter
Examples from the Corpus
patent medicine• Like a vile-tasting patent medicine, they appreciate the need for treatment, but find it hard to swallow.• Now, when I stopped at the Emporium, I looked at the patent medicine display first. 