1. Treatment of acne According to reports, 309 cases of mild to moderate inflammatory acne patients, a multi-center randomized single-blind trial, one group was given azelaic acid cream, applied twice a day, and the other group was given 5% benzoyl peroxide Gel was used as a control, and the course of treatment was 6 months. Results: In the azelaic acid cream group, the inflammatory damage was reduced by 84% compared with that before treatment, and the control group was reduced by 83%. The former had an average effective rate of 66%, while the latter was 70%, and there was no statistical significance between the two groups. Another 306 cases of mild to moderate inflammatory acne patients were randomized and double-blind. The azelaic acid cream group was applied twice a day, and the other group was given 2% erythromycin cream as a control, and the course of treatment was 5 months. Results: In the azelaic acid cream group, the inflammatory damage was reduced by 79% compared with that before treatment, and the control group was reduced by 68%. The average effective rate of the former is 71%, and the latter is 67%, indicating that the efficacy of azelaic acid cream is similar to that of erythromycin cream. According to another report, 289 cases of acne vulgaris (acne) patients were observed by random single-blind multi-center, and 0.05% retinoic acid cream was used as control. Results: The acne number in the azelaic acid group was reduced by 79% compared with that before treatment, and the control group was reduced by 82% compared with that before treatment. The average effective rate of the two groups was 65% for the former and 69% for the latter. Hjorth reported that 261 cases of severe inflammatory acne patients were treated with random double-blind multi-center treatment observation, and the control group was treated with oral tetracycline 0.5-1.0g for 6 months. Results: The inflammatory damage in the azelaic acid group was reduced by 79% compared with that before treatment, the control group was reduced by 79% compared with that before treatment, the number of cystic nodules in the azelaic acid group was reduced by 86% compared with that before treatment, and the tetracycline group was reduced by 83%. The efficiency of the former was 65%, and the latter was 69%. After statistics, the difference between the two groups was not significant.
2. In the treatment of rosacea, 146 patients with papulopustular rosacea were reported, with an average age of 49 years and a course of disease of 5.5 years. A multicenter randomized double-blind trial was used. Among them, 77 patients received azelaic acid cream, and 39 patients in the other group were treated with azelaic acid cream. Placebo control, topical application 2 times a day, 3-month course of treatment. Results: About 73% of the patients in the azelaic acid cream group had improved inflammation, but only 50.6% in the control group; the erythema severity score was reduced by an average of 47.9% in the azelaic acid group and 37.9% in the control group. Comparison, the difference is significant, but the improvement of vascular dilatation is not obvious in the two groups.
3. In the treatment of chloasma, 66 cases of facial chloasma have been reported. One group was given 1.5% azelaic acid, twice a day, and the other group of 28 cases was given 2% hydroquinone cream as a control, and the course of treatment was 3 months each. . Results: In the treatment group, 12 cases were cured, 18 cases were markedly effective, 5 cases were effective, 3 cases were ineffective, and the total effective rate was 92.1%; The difference between the two groups was extremely significant (P<0.01). No allergies and other adverse reactions were found during the treatment. Another report of 50 cases of chloasma was topical application of azelaic acid, 2 times a day, for 1 to 7 months. Results: 1 case was cured, 30 cases were markedly effective, 17 cases were effective, 2 cases were ineffective, and the effective rate was 62%.
4. Treatment of hyperpigmentation of the skin. Local application of azelaic acid cream for a long time can treat (relieve or lighten) skin melasma, senile plaques, small malignant moles, melanoma, etc. Oral administration of azelaic acid 10-15g·d-1 and topical application of azelaic acid cream can make epithelial melanoma disappear.