Acne is a chronic inflammatory skin disease of the sebaceous glands with a prevalence of 70% to 87% and a psychological and social impact on adolescents that exceeds that of asthma and epilepsy. Treatment options for acne vary widely among dermatologists, with some treatments having uncertain efficacy and lacking literature support from clinical trials; some are even harmful to patients, creating a bad social impact and causing financial damage to patients. Therefore, for clinicians who are currently practicing clinical dermatology without formal dermatology specialty training, it is essential to have a set of proven guidelines for the treatment of acne to regulate their treatment. Of course, guidelines are not set in stone, and as new evidence-based medical evidence and new drugs are developed. Acne treatment guidelines also need to be updated regularly to keep up with the times.
I. Pathophysiological factors for the occurrence of acne
The occurrence of acne is closely related to many factors such as excessive sebum production, blockage of follicular sebaceous ducts, bacterial infection and inflammatory response. The pathophysiological basis for acne is the rapid development of sebaceous glands and excessive sebum secretion, which is directly governed by androgens. After puberty, the level of androgens, especially testosterone, increases rapidly. Testosterone is converted to dihydrotestosterone in the skin by the action of 5-alpha reductase, which binds to androgen receptors in sebaceous gland cells. Elevated androgen levels promote the development of sebaceous glands and the production of large amounts of sebum. Some patients with acne have higher blood levels of testosterone than those without acne. In addition, progesterone and dehydroepiandrosterone in the adrenal cortex also have a pro-sebum effect. Sebum is mainly composed of keratins, wax esters, triacylglycerols and small amounts of sterols and cholesterol esters. Acne patients have higher levels of wax esters and lower levels of linoleic acid in their sebum, and a decrease in linoleic acid content reduces essential fatty acids around the hair follicle and promotes keratinization of the follicle epithelium.
Abnormal keratinization of the follicular sebaceous ducts is another important factor. Acne formation begins with the enlargement of the sebaceous follicles, and this enlargement is secondary to abnormal keratinization of the keratinocytes. In the lower part of the follicular funnel, the lamellar granules in the keratin-forming cells are reduced and replaced by a large number of tension filaments, bridging granules, and lipid inclusion bodies.
The secretion and discharge of large amounts of sebum are prone to bacterial infections. Various microorganisms such as Propionibacterium acnes, Staphylococcus albicans and Malassezia are present in the hair follicles, with Propionibacterium acnes infection being the most important. Propionibacterium acnes is an anaerobic bacterium, and the obstruction of sebum excretion creates a good local anaerobic environment for it to proliferate. The lipase produced by Propionibacterium acnes breaks down triacylglycerols in sebum to produce free fatty acids. The latter is the main factor contributing to the inflammatory damage of acne. In addition, P. acnes can also produce peptides that chemotactic neutrophils, activate complement and cause leukocytes to release various enzymes that induce or aggravate inflammation.
In addition to the above factors, the occurrence of acne in some patients is also related to the immune function of the body, especially in some special types of acne such as convergent acne and fulminant acne, where the immune response plays an important role.
II. Acne grading
Acne classification is an important basis for acne treatment and efficacy evaluation. According to the nature and severity of acne lesions, acne can be classified into 3 or 4 grades: Grade 1 (mild): acne only; Grade 2 (moderate): inflammatory papules in addition to acne; Grade 3 (moderate): pustules in addition to acne and inflammatory papules; Grade 4 (severe): nodules, cysts or scarring in addition to acne, inflammatory papules and pustules.
C. Local treatment of acne
1.Local cleaning
Wash your face with water to remove the mixture of oil, dander and bacteria from the skin surface, but do not over-wash. Do not squeeze or scratch the acne with your hands. In addition, avoid using oily and powdered skin care cosmetics and ointments and creams containing glucocorticoid hormone ingredients.
2.Treatment with topical drugs
(1) Vitamin A acid drugs
①0.025%～0.1% retinoic acid (all-trans retinoic acid) cream or gel: This drug can regulate the differentiation of epidermal keratin-forming cells. This drug can regulate the differentiation of epidermal keratin-forming cells and make acne dissolve and discharge. The skin is mildly irritated at the beginning of 5-12 d, such as local flushing, flaking, tightness or burning sensation, but it can gradually disappear. Therefore, it should be used from a low concentration and applied once a night. Avoid increasing drug irritation after light exposure, and apply topically once a week after symptoms improve.
②13th cis-retinoic acid gel: regulate the differentiation of epidermal keratin-forming cells and reduce sebum secretion, once or twice a day.
③2nd generation retinoids: 0.1% adapalene gel, once a night, has good efficacy in the treatment of mild to moderate acne. 0.1% tazarotene cream or gel, used once every other night to reduce local irritation.
(2) Benzoyl peroxide
This drug is a peroxide. After topical application, it can slowly release neo-oxygen and benzoic acid, which can kill Propionibacterium acnes, dissolve acne and astringent effect. It can be formulated into 2.5%, 5% and 10% different concentrations of lotions, emulsions or gels, and should be used from low concentrations. A gel containing 5% peroxymethylphenidate and 3% erythromycin can improve the efficacy.
(3) Antibiotics
Erythromycin, chloramphenicol or clindamycin (clindamycin) formulated with ethanol or propylene glycol at a concentration of 1% to 2% is more effective. 1% clindamycin phosphate solution is a water-soluble emulsion free of oil and ethanol for acne patients with dry and sensitive skin. 1% clindamycin solution is also effective.
(4) Azelaic acid
This drug can reduce the flora of the skin surface, hair follicles and sebaceous glands. In particular, it has an inhibitory effect on Propionibacterium acnes and a pimple-dissolving effect. It is effective for different types of acne. It can be formulated into a 15%-20% cream for external use, and its adverse effects are local erythema and stinging.
(5) Selenium disulfide
2.5% selenium disulfide lotion has the effect of inhibiting fungi, parasites and bacteria, and can reduce the free fatty acid content of the skin. The method of use is to clean the skin after. Apply the solution slightly diluted evenly on the obvious part of seborrhea, and then wash with water after about 20 minutes.
(6) Sulfur lotion
5-10% sulfur lotion has the function of regulating the differentiation of keratin-forming cells and reducing free fatty acids in the skin, and also has a certain inhibitory effect on Propionibacterium acnes.
IV. Antibiotic treatment for acne
Oral antibiotics are one of the effective methods for treating acne, especially moderate and severe acne. Among the many colonizing microorganisms (including Staphylococcus epidermidis, Propionibacterium acnes, Malassezia and other gram-negative bacilli, etc.). Only live Propionibacterium acnes is clearly associated with an exacerbation of the inflammatory response to acne, so it is important to select antibiotics that are sensitive to Propionibacterium acnes. In addition to infection-induced inflammation, immune and nonspecific inflammatory responses are also involved in the process of inflammatory damage in acne. Therefore antibiotics that both inhibit Propionibacterium acnes multiplication and take into account nonspecific anti-inflammatory effects should be given priority.
Combining the above factors with the pharmacokinetics of antibiotics, especially the selective distribution at the seborrheic site, tetracyclines should be preferred, followed by macrolides, and other antibiotics such as sulfamethoxazole and metronidazole can also be used as appropriate, but β-lactam antibiotics should not be chosen. Among the tetracyclines, 1st generation tetracyclines such as tetracycline are poorly absorbed orally and have low sensitivity to Propionibacterium acnes; 2nd generation tetracyclines such as minocycline, doxycycline and lymetetracycline should be preferred, and the two should not be substituted for each other. For systemic infections currently the main or commonly used antibiotics such as clarithromycin, roxithromycin, and levofloxacin are avoided.
Since antibiotics for acne mainly inhibit Propionibacterium acnes reproduction rather than non-specific anti-inflammatory effects. Therefore, it is important to prevent or slow down the development of drug resistance in Propionibacterium acnes, which requires that the dosage and regimen of antibiotics should be standardized in the use of antibiotics for acne treatment. The usual dose of minocycline and doxycycline is 100-200 mg/d, which can be taken orally once or in 2 doses; tetracycline 1.0 g/ d, taken orally in 2 doses on an empty stomach; erythromycin 1.0 g/ d, taken orally in 2 doses. The treatment course is 6-12 weeks.
Antibiotic treatment of acne should pay attention to how to avoid or reduce the development of drug resistance, including.
① Avoiding individual use to treat acne, especially long-term topical application.
② Treatment should be started in adequate doses. Maintenance should not be reduced once effective.
(③) Discontinue or switch to other antibiotics in a timely manner when there is no efficacy 2 to 3 weeks after treatment. and pay attention to patient compliance and differentiate between gram-negative bacillary folliculitis.
(iv) To ensure an adequate course of treatment. and avoid intermittent use.
⑤ Propionibacterium acnes is a parasitic bacterium of normal skin. Treatment is aimed at effectively inhibiting its reproduction, not at complete elimination, so the dose should not be increased or the course of treatment extended without principle. It should not be used as a maintenance treatment or even as a relapse prevention measure.
(6) Drug resistance of Propionibacterium acnes can be monitored if conditions permit. (6) If possible, the drug resistance of Propionibacterium acnes can be monitored to guide rational clinical use.
Adverse drug reactions should be noted in treatment, including the more common gastrointestinal reactions, drug rash, liver damage, photosensitivity reactions, vestibular involvement (e.g., dizziness, vertigo) and benign intracranial pressure elevation syndrome (e.g., headache). Rare adverse reactions include lupus-like syndrome, especially when applying minocycline, which should be used with caution or prohibited for patients with long-term alcohol consumption, hepatitis B, photosensitivity dermatitis, etc. Tetracyclines should not be used in pregnant women and children under 16 years of age. Taking minocycline daily dose orally in divided doses or using extended-release dosage form once a night may partially reduce adverse reactions. Discontinue the drug promptly when serious adverse reactions occur or are intolerable to the patient, and treat the symptoms. Both macrolides and tetracyclines are prone to drug interactions. Pay attention to drug interactions when combining with other systemic drugs.
V. Treatment of acne with retinoic acid
Oral isotretinoin is the standard treatment for severe acne, and is currently the most effective treatment for acne. Isotretinoin acts on all pathophysiological aspects of acne, and although the therapeutic effect is significant, it is not used as a treatment for mild acne because of its adverse effects. Therefore, it should not be used as the first choice for the treatment of mild acne.
The indications for the use of oral isotretinoin are
①Severe nodular cystic acne and its variant forms.
②Inflammatory acne with scar formation.
③ Moderate or severe acne that has failed to respond to the following treatments: 3 months of treatment with combination therapy. including those with systemic application of tetracyclines.
④Acne patients with severe psychological stress (disfigurement phobia).
⑤ Gram-negative bacillary folliculitis.
⑥Those who require repeated and long course systemic application of antibiotics for frequent relapses.
(vii) A few patients who need rapid healing for some reason.
Dose: The commonly used dose is 0.25-0.5 mg/(kg?d), and the dose should not exceed 0.5 mg/(kg?d) in order to reduce adverse reactions. The duration of treatment is determined by the patient’s body weight and the daily dose used. The minimum cumulative dose is targeted at 60 mg/kg, but can be increased to 75 mg/kg if the cumulative dose reaches 60 mg/kg without satisfactory efficacy. however, even if grade 1 acne is completely cleared, the probability of permanent cure is significantly reduced if isotretinoin is discontinued before reaching the 60 mg/k g domain value. There is also so-called shock therapy, which is the use of isotretinoin 0.5 mg/(kg?d) for the first 7 d of each month, which has been shown to be more effective in patients who have relapsed after having completed a full course of treatment, in those with prolonged disease and in those with treatment-resistant acne.
Under certain conditions, such as in adolescents with severe acne, continuous low-dose isotretinoin can be used. Treatment with continuous low doses of isotretinoin can be used. In these patients, acne lysis is poor in the initial phase, but isotretinoin 10-20 mg/d for a 4-6 month course can clear lesions more quickly, followed by topical retinoic acid to maintain efficacy. High-dose retinoic acid therapy is not advocated because the increase in efficacy is not significant and potentially serious toxic reactions may occur.
Counseling and interpretation of the patient prior to the systematic use of retinoic acid is very important. It should be explained to the patient that retinoic acid can cause many adverse effects, especially teratogenic effects. Patients should use strict contraception for 1 month prior to treatment and until 3 months after the end of treatment. If pregnancy occurs during the course of treatment, abortion must be managed. A small number of patients develop depressive symptoms with the use of retinoic acid. Patients with a history of depression or a family history of depression should use caution and discontinue the drug immediately in the event of mood swings or any depressive symptoms.
Other adverse effects of isotretinoin are mainly dryness of the skin mucosa. Temporary acne exacerbation may occur at the beginning of treatment. 5% of patients may experience photosensitivity, joint and muscle pain, severe night blindness during night driving, severe hair loss, and possible elevation of blood triacylglycerols. Liver function and lipid tests are performed before the start of treatment and reviewed after 1 month of treatment. If both are normal, no further hematologic testing is required. Long-term high-dose application can cause epiphyseal deformities. Such as osteomalacia, calcification of spinal ligaments, and osteoporosis. It should be noted that isotretinoin should not be applied simultaneously with tetracyclines or systemically with glucocorticoids, as isotretinoin and glucocorticoids may synergistically induce an increase in intracranial pressure. Vimentin can also be used as an alternative to isotretinoin, but it is slightly less well absorbed orally, has a slower onset of action, and has relatively milder adverse effects.
VI. Hormonal treatment of acne
1. Application of estrogens and anti-androgen drugs
(1) Estrogen
Estrogenic hormones include estrogen and progestin. It is currently believed that androgens play a role in the development of acne. Female patients with moderate or severe acne who also have high androgen levels and high androgen activity such as seborrhea, acne, hirsutism, androgenic alopecia (SAHA) or polycystic ovary syndrome (PCOS) should be treated early with estrogen and progestin. Early treatment with estrogen and progestin should be used. Combined contraceptive use may also be considered for female patients with late-onset acne and acne that worsens significantly before menstruation. The U.S. Food and Drug Administration (FDA) approves birth control pills for the treatment of acne in women >15 years of age.
Mechanism of action of oral estrogen and progestin for acne.
(1) Estrogen.
(1) By reducing the excessive secretion of androgens caused by ovarian and adrenocortical hyperfunction, as well as stimulating the synthesis of sex hormone-binding globulin (SHBG) in the liver and reducing the concentration of active androgens in the serum, they play an anti-sebaceous role.
②Estrogen can increase the amount of SHBG synthesis and decrease the amount of free testosterone.
(3) Estrogen has the effect of reducing the volume of sebaceous glands and inhibiting lipid synthesis in sebaceous gland cells.
(2) Progesterone.
①It is an inhibitor of 5-alpha reductase. It can act through negative feedback inhibition. It decreases the amount of testosterone and dehydrotestosterone in plasma.
(ii) It can inhibit the ability of sebaceous gland cells and keratin-forming cells to convert testosterone.
(3) Cyproterone acetate can also block the binding of androgens to their receptors.
(3) Estrogen and progesterone can also act directly on hair follicle sebaceous glands to reduce sebum secretion and inhibit acne production.
Oral contraceptives Oral contraceptives are a combination of estrogen and progestin. The choice of their type is also very important.
Some birth control pills contain androgens. Some synthetic progestins have cross-reactivity with androgen receptors and can lower SHBG and increase the amount of free testosterone, which can aggravate or cause acne. Currently, the drugs often chosen for acne treatment are compounded cyproterone acetate tablets (Daine-35, Diane35, each tablet contains 2 mg of cyproterone acetate + 35 μg of ethinyl estradiol), which are taken 1 tablet daily starting on day 1 of the menstrual cycle for 21 d, stopped for 7 d, and repeated for 21 d after another period, effective after 2-3 months of treatment for 3-4 months. For patients with particularly high seborrhea, the effect of conventional treatment with contraceptives is often not good, so it is possible to take 50-100 mg of cyproterone acetate on top of oral Daine-35 on 5-14 d of the menstrual cycle. The efficacy can be significantly improved. Adverse effects include small amount of uterine bleeding, breast distension, upper abdominal discomfort and facial skin redness, weight gain, deep vein thrombosis, and the appearance of melasma.
(2) Other anti-androgen treatments
Androstadienone Androstadienone, also known as spironolactone, is an aldosterone compound. Mechanism of action: ① Competitively inhibit the binding of dihydrotestosterone to the receptors of skin target organs, thus affecting its action. Inhibition of sebaceous gland growth and sebum secretion. ②Inhibition of 5-alpha reductase. Reduces the conversion of testosterone to dihydrotestosterone. The recommended dose is 1-2 mg/(kg?d) for 3-6 months. Adverse effects include menstrual irregularities (probability of occurrence is positively correlated with dose), nausea, drowsiness, fatigue, dizziness or headache, and hypercalcemia. It is contraindicated in pregnant women. It is not recommended for male patients and may cause breast development and breast tenderness after use.
Metacycline (cimetidine) has a weak anti-androgenic effect, competitively blocking the binding of dihydrotestosterone to its receptors without affecting serum androgen levels, thereby inhibiting sebum production. The recommended dose is 200mg, 3 times daily, for 4-6 weeks.
2.Application of glucocorticoids
Glucocorticoids have the functions of inhibiting androgen secretion caused by hyperadrenocorticism, anti-inflammation and immunosuppression.
Oral glucocorticosteroids are mainly used for fulminant acne or coalescent acne because these types of acne are often related to excessive immune and inflammatory reactions. However, it should be noted that glucocorticosteroids themselves can induce acne. Oral administration should only be used in patients with more severe inflammation and in small, short-term doses.
Recommended dosage.
①Fulminant acne: Prednisone 20-30 mg/d for 4-6 weeks, followed by a gradual reduction over 2 weeks and the addition of oral retinoic acid.
(ii) Aggravation of coalescent acne or violaceous acne occurring during oral treatment with retinoic acid. Give prednisone 20-30 mg/d for 2-3 weeks, then taper the dose over 6 weeks; also discontinue oral retinoic acid or reduce the dose to 0.25 mg/kg/d, then increase or decrease the dose according to the condition.
③ Prednisone 5 mg/d or dexamethasone 0.375-0.75 mg/d, taken every night, can inhibit the high secretion of pro-adrenal hormone early in the morning and inhibit the production of androgens by the adrenal glands and ovaries, and gradually reduce the dose after improvement. For patients with acne that worsens before menstruation, prednisone 5 mg/d can be taken 10 d before menstruation until the onset of menstruation. Fisher et al. believe that high doses of glucocorticoids have anti-inflammatory effects, while low doses have anti-androgenic effects.
VII. Herbal treatment of acne
Chinese herbal therapy should be divided into types of treatment and added or subtracted according to the symptoms. The treatment of red papular acne is recommended to clear the lungs and stomach; the treatment of pustular acne is recommended to detoxify and disperse the knots; the treatment of premenstrual acne is recommended to regulate the flushing method; the treatment of aggregated acne, post-pigmentation or scarring is recommended to activate blood and disperse stasis.
Acupuncture and moxibustion therapy: The acupuncture points of Dazhi, Spleen Yu, Foot San Li, Hegu and Sanyinjiao are often selected.
Ear acupuncture therapy: the patient’s bilateral ear lung points as the main points, with the Shen Men, sympathetic, endocrine, subcortical points buried Wang Bu Liuxing seeds, external fixed with adhesive tape, massage the upper points 3 times a day, about 10 min each time.
Diet therapy: patients should eat less high sugar, high fat, wine, spicy and other stimulating food, eat more vegetables (bean sprouts, bok choy, tarragon, winter melon, loofah, bitter melon, water chestnut) and fruits. Drink mung bean soup regularly to clear lung heat and remove dampness and toxicity. Eat more food containing long fiber to keep the bowels open, which is effective in preventing acne. In addition, avoid using oil, powder, cosmetics and ointments and creams containing hormonal ingredients. Wash your face twice a day with warm water, do not use strong alkaline soap, wipe away facial fat and dirt when washing, prohibit your fingers from squeezing facial papules, pimples and pustules to prevent scarring, and ensure adequate sleep. Adjust the function of the digestive system, all of which can help to cure acne.
Eight, acne physical therapy
For acne patients who cannot tolerate medication or do not want to accept medication, physiotherapy is the best choice. Physiotherapy is the best choice. At present. Commonly used physical therapy for the effective treatment of acne are photodynamic therapy, laser therapy and fruit acid therapy.
1.Photodynamic therapy (PDT)
Use specific wavelengths of light to activate the porphyrins metabolized by Propionibacterium acnes. Through phototoxic reactions, inducing cell death and stimulating macrophages to release cytokines and promote self-healing of lesions to achieve the purpose of acne treatment. At present, blue light alone (415nm), blue light combined with red light (630nm) and red light + 5-aminoketovaleric acid (5-ALA) are mainly used to treat various types of acne vulgaris. Treatment protocol: 1-2 times per week. Blue light energy is 48 J/cm2, red light is 126 J/cm2, 4-8 times for a course of treatment. There was slight itching during the treatment, and some patients showed slight flaking after the treatment, and no significant adverse effects were found. The experiment proved that photodynamic therapy can inhibit sebaceous gland secretion, reduce the number of acne and inflammatory lesions, and promote tissue repair to varying degrees.
2.Fruit acid therapy
Fruit acids are widely found in nature in fruits, sugar cane and yogurt. The molecular structure is simple and the molecular mass is small. Non-toxic and odorless, strong permeability, safe action. It does not damage the epidermal barrier function. The mechanism of action of fruit acids is to reduce the adhesion of keratin-forming cells by interfering with the binding force on the cell surface, accelerating the shedding and renewal of epidermal cells, while stimulating dermal collagen synthesis and enhancing moisturizing function. The higher the concentration of fruit acid, the longer the action time, the better its effect, but the relative adverse effects are also greater. Treatment protocol: Apply fruit acids (hydroxyacetic acid) at concentrations of 20%, 35%, 50%, and 70% once every 2-4 weeks for acne treatment, with 4 times being a course of treatment. Inflammatory lesions and non-inflammatory lesions had varying degrees of regression. The regression rate is 30% to 61%. Increasing the number of treatments can improve the efficacy.
3.Laser therapy
1450 nm laser, Intense Pulsed Light (IPL), pulsed dye laser and fractional laser are among the effective methods to treat acne and acne scarring. The 1450 nm laser is approved by the U.S. Food and Drug Administration (FDA) for the treatment of acne. Intense pulsed light can help fade the red marks in the later stages of inflammatory acne. Fractional laser has a certain degree of improvement for acne scarring.
4.Other treatments
①Pimple picking This is one of the current effective methods of acne treatment, but it is necessary to use medication at the same time to fundamentally inhibit the production and development of acne.
②Glucocorticoid injection in nodules and/or cysts helps to rapidly eliminate inflammation and is a very effective treatment for larger nodules and cysts.
③ Cyst excision and drainage: For large cysts, excision and drainage is an effective way to avoid later lesion mechanization and formation of scarring.
9. Grading of acne treatment
The grading of acne reflects the severity of acne and the nature of the lesions, so the treatment of acne should be based on the grading of the corresponding treatment drugs and methods. Whether the classification is based on the number of lesions, the International Modified Classification. Whether acne is graded according to the International Modified Classification, which is based on the number of lesions, or the Acne Classification, which emphasizes the nature of the lesions, the treatment options are basically the same. Of course, the treatment plan for acne is not set in stone and should be flexible according to the actual situation of the patient, fully reflecting the principle of individualized treatment.
Grade 1: Topical treatment is generally used. If only acne is present, topical vitamin A acid preparations are the best choice. Some medical skin care products that have the effects of exfoliating, dissolving acne, inhibiting sebum secretion, and antibacterial can also be used as an adjunctive treatment.
Grade 2: Treatment for grade 1 acne is usually used, but for inflammatory papules and pustules more often. Oral antibiotics may be used to treat those who have had poor results with topical treatment. This type of acne can also be treated with combination therapy, such as oral antibiotics combined with topical retinoic acid preparations, or combined application of physical therapy such as blue light, photodynamic therapy, or fruit acid therapy.
Grade 3: Such patients often need to adopt a combination treatment approach, in which the systematic use of antibiotics is one of their basic treatment methods. And it is important to ensure an adequate course of treatment. The most frequently used combination therapy is oral antibiotics combined with topical retinoic acid preparations, and also topical peroxymethylphenidate can be used at the same time. Hormonal therapy has also been used with good results in female patients who require contraception or have other gynecologic indications. Other combination therapies described in this guideline may also be used. Such as red and blue light and photodynamic therapy, but attention should be paid to the interactions and contraindications between tetracyclines and isotretinoin drugs, as well as the development of photosensitivity. Those with poor results can be treated with oral isotretinoin alone or with concomitant topical peroxynivalenol. For those who need more than 3 months of systemic antibiotic application, it is necessary to combine such antibacterial agents that do not cause bacterial resistance as peroxymethol to prevent and reduce the development of drug resistance.
Grade 4: Oral isotretinoin is the most effective treatment for this group of patients and can be used as first-line therapy. For patients with more inflammatory papules and pustules, a combination of systemic antibiotics combined with peroxynivalenol can also be applied first, and then switched to oral isotretinoin for lesions such as cysts and nodules after the lesions have improved significantly. The methods used for Grade 3 acne above and the combination therapy described in this guideline can also be tried.
Regardless of the grade of acne. It is important to maintain treatment after symptoms have improved.
X. Combination therapy for acne
The combination of oral antibiotics and topical retinoic acid can have a synergistic effect through their different pathways of action. The combination of these two methods can clear lesions faster than antibiotics alone for inflammatory damage and acne. Also topical retinoic acid can shorten the duration of antibiotic treatment, increase antibiotic penetration and increase follicular cell turnover, thus allowing more antibiotics to reach the sebaceous units and reducing the incidence of drug resistance.
Combination therapy is now the standard of care for mild to moderate acne. The advantages of combination therapy are.
(i) The clinical efficacy of antibiotics combined with topical retinoic acid is significantly better than that of antibiotics alone.
(ii) Faster onset of action on inflammatory damage and acne.
(iii) The ability to target different pathophysiological factors.
④ Topical retinoic acid can increase the penetration of antibiotics and promote the rapid action of antibiotics.
Principles of combination therapy.
① oral antibiotics combined with topical vincristine can act on 3 pathogenic factors.
② oral antibiotics should not be combined with topical antibiotics (which can increase bacterial resistance without increasing efficacy).
(iii) The incidence of drug resistance can be reduced by combining peroxybenzoyl or topical retinoic acid with oral antibiotics.
(iv) Topical peroxymethol should be combined with antibiotics when prolonged use is required.
⑤ The combination of topical retinoic acid and benzoyl peroxide can be used daily with one or both drugs alternately in the morning and evening.