Abstract:
Background: Post inflammatory hyperpigmentation was the popular problems in dermatology department. Especially post inflammatory hyperpigmentation from Acne Vulgaris in Asian. Previous study demonstrated that Nicotinamide inhibits melanosome transfer from melanocytes, the key enzyme in melanogenesis and also has anti-inflammatory, sebum-control effect which are Acne Vulgaris relieving factors.
Objectives: To compare the effectiveness between 2% and 4% nicotinamide cream on the treatment of post inflammatory hyperpigmentation from acne vulgaris.
Material and Methods: Eighteen Thai volunteers with post inflammatory hyperpigmentation from acne vulgaris were enrolled. Using 2% nicotinamide cream and 4% nicotinamide cream for treatment of post inflammatory hyperpigmentation from acne vulgaris Creams were randomly applied both sides of face, used block randomization, in a split face design (right and left sides), twice daily for 12 weeks. Post Inflammatory hyperpigmentation was evaluated at 1st, 4th, 8th and 12th by using mean melanin index measured by mexameter MX18. Volunteers side effect was assessed by questionnaires and physician observation. Photographs from VISIA® Complexion Analysis System at 0th (before treatment) and at 1st, 4th, 8th, and 12th weeks were compared and scored evaluation scales by 3 dermatologists. Volunteer satisfaction was evaluated at 12th week by questionnaires.
Results: Seventeen volunteers completed the study. Mean melanin index of the sides that applied 4% Niacinamide cream were lower than 2% Niacinamide statistically significant at 4th week (Mean ± S.D, 311.88 ± 90.31, 293.29 ± 86.86, p-value = 0.008). Mean melanin index of the sides that applied 4% Niacinamide cream were statistically significant reduction from the baseline from 4th week of application. (Mean ± S.D, 293.29 ± 86.86, p-value=0.014). Therefore, 2% Niacinamide cream were statistically significant reduction from the baseline from 12th week. (Mean ± S.D, 301.82 ± 95.67,p-value = 0.028). The dermatologist evaluation and volunteer satisfaction rated for both sides as moderately satisfied. Only one volunteer (5% from volunteers) was found the side effects from Niacinamide cream application which mild condition and resolved after dropped off from this study, There were pruritus and erythematous rashes. Side effects were not difference between 2% and 4% Niacinamide application.
Conclusion: The results of the study clearly demonstrated that 4% nicotinamide has significant reduce Post Inflammatory Hyperpigmentation from acne vulgaris compare with 2% Nicotinamide. These can be used as alternative treatment for Post Inflammatory Hyperpigmentation from acne vulgaris.