NEWPORT BEACH, CALIF. Light therapy with a photosensitizing agent is an effective treatment for acne vulgaris and provides an important alternative to other approaches, Dore Gilbert, M.D., said at a meeting sponsored by the Foundation for Facial Plastic Surgery.
Though treatment with retin-A compounds is the front-line option for most dermatologists who have patients with sebaceous acne, this is another way to see visible improvementand to satisfy patients, said Dr. Gilbert, who practices in Newport Beach, Calif. "It is not a cure, but we do see a long-term deterrence of the condition."
Current drug therapies for acne have side effects, and some adolescents cannot tolerate them, he observed. However, there are no such concerns with light therapy. By adding levulinic acid to the regimen, "you get a much quicker response and better skin texture changes," he said. The effect on the sebaceous gland is fairly well documented: Light activation in the presence of a photosensitizing agent diminishes the sebaceous product inside the pustule and kills the bacteria thriving in it. Shrinkage occurs quickly, Dr. Gilbert said.
The term photodynamic therapy was coined a century ago by German scientists who observed that targeted light benefited certain skin conditions, including acne. Only a few decades ago, it was not unusual to see adolescents with serious involvement who suffered periodic sunburns, thanks to popular home treatments with a UV lamp. Now, with the addition of photosensitizing compounds to activate certain target cells, the administration of light is proving much safer than, and just as effective as, some topical treatments, Dr. Gilbert said at the meeting, which was also sponsored by Medical Education Resources.
He has treated patients with the combination of a photosensitizer and both blue light and intense pulsed-light therapy. Significant clearance with a few treatments, sometimes only one, is achieved about 75% of the time in patients with cystic or superpustular acne, he said. About 50% of his patients have had a quantifiable decrease in pore size.
The photosensitizing compound needs to be activated by wavelengths with good penetration of the skin, he advised. Any wavelength in the range of 415640 nm seems to work well. Moreover, any type of light source will work in this wavelength zone. Dr. Gilbert said he has relied mostly on blue light and intense pulsed-light lasers. In some cases, a combination of these two is substantially better than either alone, he noted.
Dr. Gilbert recommends using a facial scrub with acetone followed by application of the photosensitizer, which can be left on for at least an hour prior to light treatment. The chemical photosensitizing compound should be one that metabolizes well over a 60-minute waiting period. This should give it significant intracellular photodynamic properties with the introduction of light. The process should result "in rapidly dividing target cells and have a short time between administration of compound and accumulation in the target cells," he said.
"One downside to phototherapy is that for 34 days there is redness and scaling," he pointed out. "That can be tough for kids in school." He tries to schedule these patients so that their recovery time does not coincide with school days.