Photodynamic therapy with low-strength ALA, repeated applications and short contact periods (40-60 minutes) in acne, photoaging and vitiligo.

Topical aminolevulinic acid (ALA) photodynamic therapy (PDT) is currently being used for the treatment of actinic keratosis of the face and scalp. This study reports the results obtained after three to four treatments with ALA-PDT in patients with acne (n=12), photoaging (n=8) and vitiligo (n=6). ALA was applied on large areas (e.