White patches on hands — vitiligo; tacrolimus + phototherapy. Acne vulgaris (teens — comedones, papules — face: benzoyl peroxide, topical retinoids; moderate — doxycycline; severe — isotretinoin — teratogenic — pregnancy test): rosacea (adults — flushing, telangiectasia — triggers — alcohol: metronidazole, doxycycline). Vitiligo (depigmented — autoimmune — thyroid: tacrolimus — face; phototherapy — NBUVB; grafting — stable): melasma (facial brown — pregnancy/sun: sunscreen — strict; hydroquinone, kojic). Sunscreen is treatment — pigmentation needs it.