Eye drops are sterile topical liquids that are used directly in the eye. Eye drops are sterile solutions obtained by dissolving drugs and additional agents in water, filtering and sterilizing them. Because the eyes are very sensitive and delicate, especially when suffering from eye diseases, they are more sensitive to external stimuli. Therefore, eye drops must be stable, sterile, free of foreign substances, and painless and non-irritating when used. The quality requirements of eye drops are indeed very strict, but if they will not be used correctly, not only will they fail to achieve the therapeutic effect, but also adverse reactions may occur. The correct way to use eye drops. 1, before using the medicine should check whether the name of the medicine used is correct, do not order the wrong medicine. 2. Wash your hands before applying the drops, either in a supine or sitting position with your head slightly tilted back, gently pull the lower eyelid into a bag with your left hand, and then gently lift the lower eyelid to cover the eye after applying 1 drop of eye drops to the bag, so that the drops fill the entire conjunctival sac. Close the eyes for at least 1 to 2 minutes after the drops are applied. 3. Do not put the drops directly on the cornea and do not forcefully close your eyes after putting the drops in to prevent spillage of the drops. 4. 1 drop of eye drops is enough for each application, not too many, otherwise the solution will spill out. Some eye drops are suspensions (e.g. cortisone drops), which should be shaken well before use to avoid affecting the efficacy. 6. If several eye drops are to be used, there must be an interval (15 minutes or so) between the two types of drops before and after, and not at the same time, otherwise the efficacy will be affected and even adverse reactions will occur. 7, some eye drops must be carefully operated when used (such as atropine, pilocarpine, etc. have a certain degree of toxicity), eye drops should avoid eye drops through the tear duct into the tear sac and nasal cavity, be absorbed and cause poisoning. 8. Do not let children use eye drops on their own, and eye drops must be given to children by adults to avoid adverse events.