1. Acne is a chronic inflammatory disease involving the hair follicles and sebaceous glands, characterized by acne, papules, pustules, nodules, and cysts. Acne often occurs in sebum overflow areas such as the face, chest, back and so on. It is a common skin lesion, which not only affects physical health, but also brings psychological disorders and psychosocial problems to patients. At present, the common treatment methods of acne include health education, topical drugs, oral drugs and medical cosmetic treatment.
2. Intense pulsed light has been widely accepted as a non-invasive and non-serious treatment for acne. The M22 strong light and laser system Acne filter has a wavelength of 400-600/800-1200nm.
3. Although there are many treatments for acne, the slow response and easy recurrence of acne are still common problems that trouble doctors and patients. We clinically use drugs combined with intense pulsed light treatment, and the efficacy of the patients is fair, but currently lack of clinical research data support. This study intends to evaluate the effectiveness of different methods in the treatment of moderate and severe acne by evaluating different bands of intense pulsed light combined with drugs, and to observe whether the treatment with oral tetracycline antibiotics combined with intense pulsed light is safe.

The M22 strong light and laser system Acne filter has a wavelength of 400-600/800-1200nm. The light in the 400-600nm band is targeted at the superficial skin inflammation, while 800-1200nm is targeted at the deep sebaceous gland inflammation. The skin can produce oxidation reaction to form singlet oxygen to eliminate propionibacterium acnes after absorption of porphyrin at 400nm. The light of 800-1200nm band can penetrate into the deep layer of sebaceous glands, and the thermal contraction of sebaceous glands can improve the anaerobic environment of bacteria, which is not conducive to the reproduction of bacteria. Meanwhile, when the temperature of sebaceous glands reaches 40 degrees Celsius, bacteria can be killed directly.

Inclusion Criteria:

• Age 18-40, regardless of gender; The patient agrees to participate in this trial and signs the informed consent Clinical diagnosis of acne (moderate and severe) No bleeding, rupture, infection or other conditions affecting the visual field of laser surgery.

Exclusion Criteria:

• Persons with facial dermatitis and sensitive skin; Relevant treatment within 1 month, including topical drugs, oral drugs, medical cosmetic treatment; Those with a history of exposure to the sun in recent January; Persons with scar constitution; Skin malignant tumor or precancerous lesion; Diabetes, heart disease, epilepsy, connective tissue disease, etc.; Pregnant or breastfeeding; Recent skin infections (such as viruses; Bacteria); Those who are using other methods to treat similar diseases; Others are not suitable for enrollment.