Fifteen minutes of laser light can control acne for up to three months, a new British study says.

Dermatologists at Hammersmith College of Medicine used a pulsed-dye laser, a standard piece of equipment in many dermatology centres but one that has not been aimed at acne, says a report in the Oct. 25 issue of The Lancet.

A welcome development
We found it to be a very effective treatment, says Dr Edward Seaton, a clinical research fellow in dermatology at Hammersmith and a co-author of the small study. The acne melted away.

Effective laser treatment for acne would be a welcome development, Seaton says, because resistance is developing against the antibiotics now used against the condition, and Reaccutane, a widely used non-antibiotic drug, has been reported to have psychological effects.

Pulsed-dye lasers emit visible light that is absorbed by haemoglobin, so they have been used to treat port wine stains and other blood-related skin conditions. They also can reduce fine wrinkles and scars caused by severe acne. The Hammersmith trial was based on observations that some patients getting treatment for those conditions had striking and longstanding improvements in inflammatory acne, the journal report says.

The research study
The study included 41 people with mild to moderate acne, ranging from teenagers to some in their 40s. Only 31 got the laser zaps; the other 10 were given sham treatment to serve as a control group.

Over the next three months, acne severity was halved in the people who got the real treatment, with no change in those who got the fake therapy. One zap doesn’t cure the condition, Seaton says. It controls it. Patients respond for two to three months, then get problems again and must have another treatment.

More research is needed on more patients, Seaton says, in part because it’s not clear yet why laser light is effective against acne. We’re looking at the way the lasers work, trying to find the mechanism, he says.

Little side effects
There are several reasons to hope that laser treatment proves out, Seaton says. Its effects were felt almost immediately in the study, while it takes six to eight weeks for current treatments using antibiotics and lotions to take effect. Medications must also be taken every day and can have bothersome side effects. The only side effect of the laser treatment was brief discomfort in two patients.

Laser treatment for acne seems reasonable, says Dr Claudia Hernandez, a professor of medicine in the dermatology department of Loyola University Health System. But a lot of questions must be answered first, she adds.

Questions remain unanswered
This was a small study, and the number of control patients was small, Hernandez says. We don’t have a long-term follow-up. Would combination therapy be effective? We might have a study to see what the optimum dosage is. And what would the eventual cost of treatment be?

Caution is also expressed by Dr Guy Webster, a professor of dermatology at Jefferson Medical College in Philadelphia, in an accompanying editorial.

Infrequent treatments that make drugs unnecessary would benefit all concerned (except drug companies), Webster writes. But we are not yet at the point where acne patients are going to throw out their antibiotics and line up for the laser. More work is certainly needed, both to confirm the clinical benefit and best regimen and to elucidate its mechanism.