Although larger trials are pending, PDT may serve as a safe and effective alternative to isotretinoin in patients who are recalcitrant to conventional acne treatments, and may also be a cost-effective one, depending upon the comparative need for retreatment. Analysis of costs indicates that three ALA-PDT sessions with is higher than the cost of 5 months of isotretinoin therapy. However, in addition to the isotretinoin costs, the cost must be added of six sets of blood pregnancy tests, oral contraceptives, and office visits to an obstetrics and gynaecology specialist and to a dermatologist.
In addition, costs related to the potential toxicity of isotretinoin must also be computed. The overall cost of three ALA-PDT sessions is then less than that of a 5-month isotretinoin regimen. The cost of frequency of retreatment is an important comparison than cannot be made until further data are collected. Longer follow-up intervals beyond 13 months are necessary to further assess whether the long-term cost of PDT remains less than that of a course of isotretinoin.