The OTC logo usually refers to over-the-counter drugs, which can be purchased and used through independent judgment without a prescription from a licensed physician or a licensed assistant physician. The OTC logo is divided into red and green, with red being Class A non-prescription drugs and green being Class B non-prescription drugs, and there are certain differences between the two types of drugs in terms of purchase channels, safety and guidance for purchase: 1. 2. Safety: Usually OTC drugs with green OTC logo are safer and have fewer side effects than those with red OTC logo, so they have less impact on the organism; 3. The green OTC labeled drugs can usually be purchased and used without the guidance of a physician or medical practitioner. Regardless of which drugs with the OTC logo are drugs rather than health care products, so patients are advised to choose their medications under the guidance of a doctor to avoid other adverse reactions or aggravation of their condition due to incorrect use.