During the use of eye drops, if mild pain or irritation occurs, it is a normal reaction that lasts for a short period of time, perhaps only a few seconds or minutes, and does not require treatment and does not affect the use of the drug. However, if the eye drops, such as bear bile drops, are accompanied by pain or other symptoms, such as loss of vision or watery eyes, it may be an adverse reaction to the drug or an allergy to the drug. It is recommended to stop the use of the drug as soon as possible. It is necessary to rinse the eyes with water to flush out the eye drops that have been ordered into the eyes to avoid further effects on the cornea or conjunctiva, and to go to the hospital for a detailed examination.