The small pimples that appear all over the face after the water light injection may be caused by hyaluronic acid not being absorbed in time and skin allergy, which can be improved by streamlining skin care or using drugs. 1. Hyaluronic acid is not absorbed in time: when the patient just injected hydrafacial injection, due to the slow absorption of hyaluronic acid in some patients’ skin, there may be a small pimples all over the face, this situation does not need to be overly worried about, with the gradual absorption of hyaluronic acid, the small pimples will subside on their own, the patient can do a good job of streamlining the skin care in the day-to-day. 2. Allergic reaction: If the allergy to the components of the hydrafacial injection may cause a small pimple all over the face, at this time the patient can be under the guidance of the doctor oral desensitization drugs, such as levocetirizine hydrochloride, olopatadine hydrochloride, and so on. If there is still a rise in body temperature, breathing difficulties and other problems, must go to the hospital in time. When patients injected with hydrafacial injection full of small pimples, it is recommended to go to the regular hospital in time for examination and symptomatic treatment under the guidance of a professional doctor.