Acne is a chronic inflammatory skin disease that takes different amounts of time to treat depending on its severity. Most patients need treatment for 1-12 months to get better, while some patients may need several years to get better. Severe patients will be left with scarring, which is difficult to completely eliminate. 1. Mild acne: mainly blackheads and pimples, which can be treated with topical creams, usually with better results within 1 month; 2. Moderate acne: such as inflammatory papules, which can significantly improve symptoms after anti-inflammatory treatment for about 2 weeks, with red pimples The color becomes darker and gradually flattens out. After 2-3 months, the acne marks are basically absorbed and gradually return to normal skin; 3. Severe acne: If cysts and abscesses appear, the treatment time is longer, with 6-8 weeks before the initial treatment effect is revealed. It takes 3 months for nodules and cysts to subside, and the recovery period takes 6-12 months. Some patients with severe acne may take several years to improve, leaving scarring after the condition has stabilized, and the facial skin usually does not return to a completely flat state. Daily care also affects the healing rate of acne. Patients are advised to eat a light diet, eat more vegetables and fruits, try not to eat spicy and stimulating foods and foods with a lot of sugar and fat, keep bowel movements smooth, and actively cooperate with treatment; keep your mood relaxed and avoid excessive fatigue. According to individual circumstances, medication or red and blue light irradiation and photodynamic therapy can be used to help promote the recovery of acne and the flattening of the scar.