BackgroundSocial media has emerged as a common source of dermatological information. Monitoring the patterns of social media use and engagement is important to counteract the limitations of social media. However, evidence in Vietnamese dermatology patients is lacking.ObjectiveThis study aimed to explore social media use and engagement by dermatology patients and to identify factors associated with social media use and engagement.MethodsA cross-sectional study was conducted with 519 participants at the Vietnam National Hospital of Dermatology and Venereology during September to November 2018. Data about sociodemographic characteristics, social media use, and social media engagement were collected. Multivariate logistic and tobit regression models were used to identify factors associated with social media use and engagement.ResultsInterest in information about “cosmetic, beauty, and skincare techniques” was the greatest (184/519, 46.2%). The mean engagement score was 8.4 points (SD 2.4 points). Female patients were more likely to use social media (odds ratio [OR] 2.23, 95% CI 1.23-4.06) and be interested dermatological information on social media (OR 3.09, 95% CI 1.35-7.09). Women also had higher social media engagement scores (coefficient=0.68, 95% CI 0.17-1.18). Higher social media engagement scores were related with Instagram use (coefficient=0.58, 95% CI 0.00-1.15) and higher credibility scores for “family members” (coefficient=0.15, 95% CI 0.03-0.26) and “dermatology companies” (coefficient=0.22, 95% CI 0.04-0.39).ConclusionsThis study discovered high social media usage among dermatology patients. However, only moderate utilization and credibility levels were reported regarding the use of social media as a source of dermatological information. More efforts should focus on involving dermatologists in the development of individualized information on social media targeting specific groups of dermatology patients.