Those cough drops listed below as "gluten-free" should meet the U.S. Food & Drug Administration gluten-free standard, which requires them to contain less than 20 parts per million (PPM) of gluten.

These cough drops are made from honey, vitamin D, and zinc. Worth noting, per Dr. Watkins: Some data has even suggested that taking zinc at the start of a cold can help shorten your symptoms by a day.