There are more hazards and after-effects of hair transplantation, which may include local trauma, follicular atrophy, and numbness in the back of the head. 1. Local trauma: In the process of hair transplantation, if you don’t pay attention to the way and method or improper operation, local injury is easy to cause redness and pain in the scalp. You can use antiseptic water to scrub, and then apply Bactroban ointment, which has anti-inflammatory and bactericidal effects. 2. Hair follicle atrophy: improper operation of hair transplantation is more damaging to the hair follicle tissue, easy to cause hair follicle atrophy, the surrounding hair can not grow normally. After hair transplantation, you can massage the scalp to promote the normal development of hair follicles. 3. Numbness in the back of the head: If you are worried about pain during hair transplantation, anesthesia injection is usually recommended, and some patients may cause anesthesia reaction after the operation, resulting in numbness in the scalp, and the symptoms may extend to the back of the head. Under normal circumstances, the anesthetic reaction will return to normal after it disappears. If the nerves are injured, you should follow the doctor’s instructions to take oral glutamine to nourish the nerves. Hair transplantation must be carried out under the guidance of a professional doctor. After hair transplantation, if there is any adverse reaction, you should consult a doctor in time.