Postinflammatory hyperpigmentation: A comprehensive overview Treatment options and prevention Suteeraporn Chaowattanapanit, MD, a,b Narumol Silpa-archa, MD, a,c Indermeet Kohli, PhD, a Henry W. Lim, MD, a and Iltefat Hamzavi, MD a Detroit, Michigan, and Khon Kaen and Bangkok, Thailand Postinflammatory hyperpigmentation (PIH) occurs after various dermatoses, exogenous stimuli, and dermatologic procedures. The clinical course of PIH is chronic and unpredictable, although the probability of resolution of epidermal hyperpigmentation is better than those of dermal hyperpigmentation. PIH can be prevented or alleviated. When it does occur, the underlying inflammatory conditions should be sought and treated as the first step to reduce the progression of inflammation and PIH (which is an inflammatory consequence). If the inflammatory conditions subsides or there is no evidence of inflammation at the time of diagnosis, the treatments of PIH should be considered as the next step. Understanding the available treatment options helps the physician choose the appropriate treatment for each patient. Having a reproducible model for PIH is essential for the development of treatment modalities. The second article in this 2-part continuing medical education series on PIH specifically addresses the evidence that supports medical and procedural treatments of PIH and other forms of acquired hyperpigmentation. It also describes a PIH model and provides an algorithm for clinical practice along with discussion about the prevention of PIH. ( J Am Acad Dermatol 2017;77:607-21.) Key words: bleaching agent; botanical; chemical peeling; hydroquinone; hyperpigmentation; laser and light; melanin; photoprotection; sunscreen; trichloroacetic acid. Learning objectives After completing this learning activity, participants should be able to describe currently available medications, surgical treatments, and laser treatments for PIH; list possible side effects for PIH medication, surgical treatment, and laser treatment regimens; and discuss photoprotection methods to alleviate the PIH. Disclosures Editors The editors involved with this CME activity and all content validation/peer reviewers of the journal-based CME activity have reported no relevant financial relationships with commercial interest(s). Authors The authors involved with this journal-based CME activity have reported no relevant financial relationships with commercial interest(s). Planners The planners involved with this journal-based CME activity have reported no relevant financial relationships with commercial interest(s). The editorial and education staff involved with this journal-based CME activity have reported no relevant financial relationships with commercial interest(s). From the Department of Dermatology, a Henry Ford Hospital, Detroit; Department of Medicine, b Faculty of Medicine, Srina- garind Hospital, Khon Kaen University; and the Department of Dermatology, c Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok. Drs Chaowattanapanit and Silpa-archa contributed equally to this article. Funding sources: None. Dr Kohli is a subinvestigator for Ferndale Laboratories, Estee Lauder, Johnson & Johnson, and Allergan, and is a consultant for Pfizer. Dr Hamzavi is an investigator for Clinuvel, Estee Lauder, Allergan, Ferndale Laboratories, and Johnson & Johnson, and is a consultant for Aclaris Therapeutics. Dr Lim has served as a consultant for Pierre Fabre and is an investigator for Clinuvel, Estee Lauder, and Ferndale Laboratories. Drs Silpa-archa and Chaowattanapanit have no conflicts of interest to declare. Accepted for publication January 22, 2017. Reprint requests: Iltefat Hamzavi, MD, Department of Dermatology, Henry Ford Medical Center e New Center One, 3031 W Grand Blvd, Ste 800, Detroit, MI 48202. E-mail: ihamzav1@hfhs.org. 0190-9622/$36.00 Ó 2017 by the American Academy of Dermatology, Inc. http://dx.doi.org/10.1016/j.jaad.2017.01.036 Date of release: October 2017 Expiration date: October 2020 607