If you already have a suntan, hair removal is not recommended basically. This is because pigments in the treated area may result in pigment loss or hyper-pigmented. Especially, in the case of the lower limb (knee), it may come out like a zebra pattern.
There are risks also in the case of the face, but in the event that it is absolutely necessary, after considering the risk sufficiently. YAG laser might be slightly safer for those people.
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