[Post-inflammatory hyperpigmentation occuring after cosmetic procedures]

A post-inflammatory hyperpigmentation (PIHP) can occur after cosmetic procedures such as chemical peels and lasers. Patients must be informed about this risk. Precautionary measures before, during and after the procedure can prevent or reduce the risk of PIHP. These procedures should not be done in summer on suntanned skin and patients have to be aware of the importance of an effective photoprotection. The PIHP occurs more frequently on dark-skinned patients, in Asians as well as in women with melasma history. In these cases, risk/benefit assessment of the cosmetic procedure is required: no risky procedure in patients at risk! PIHP can also be related to technical errors such as too high concentration or too long exposure time during peel procedure as well as excessive threshold fluences during laser procedure. If many therapies for PIHP damages can be proposed, patients feel frequently that they are not as quickly effective as they would like. Patients must be reassured as many PIHP resolve spontaneously. If photoprotection is always required, it is also possible to accelerate the pigmentation's clearing using the Kligman trio or the numerous topical lightening agents targeting several steps of the hyperpigmentation process. More invasive and expensive therapies such as peels, lasers, IPL or radiofrequency might be used for refractory cases. As a pigmentary relapse might occur after these procedures, the traditional Kligman trio should be always considered.