Hello, OTC drugs are over-the-counter drugs, which are relatively safe and can be purchased by customers themselves. RX is a prescription drug, but it is not labeled on the packaging. You must have a prescription before you can buy it. R (circled) refers to the registered trademark of the product. For example, Gankang, a cold medicine, is its trade name, with a circled R mark next to it, and its generic name is Compound Paracetamol Tablets. Aspirin is an antipyretic and analgesic and is a prescription drug. I hope it will be helpful to you