According to a study published in pretigious medical journal, The Lancet, British doctors recruited 41 adults who had mild to moderate facial inflammatory acne, and gave a single session of pulse-dye laser to 31 of them, and a sham treatment to the other 10.
At a follow-up assessment three months later, acne symptoms among the laser group were found to be only half as bad as before, while amongst the sham group, there was no change in severity at all.
In addition to this improvement, the laser group suffered no adverse side effects at all.
Pulse-dye laser is already used to treat cosmetic problems such as birth marks, fine facial wrinkles and scars left by acne. This is the first research to test anecdotal evidence that lasers can also address the acne itself.
The disease is caused by a bacterium, Propionibacterium acnes, which proliferates in skin follicles that are clogged by excessive sebum or dead skin cells. That unleashes an attack on the bacteria by T-cells in the body's immune system, leading to lesions.
In the worst cases, acne scarring can be so bad that people's lives are quite crippled and some are even driven to suicide.
Lead researcher Tony Chu, a consultant dermatologist at London's Hammersmith Hospital, said the results from this small-scale study are so encouraging that pulse-dye laser has the potential to be an accompaniment, or even a substitute, for acne creams and oral antibiotics.
Skin creams are messy and can cause irritation, while some kinds of antibiotics are now immune to certain strains of P. acnes. Both options can drag on for weeks at a time and are relatively expensive.
A cautious note is sounded, though, by US specialist Guy Webster, who notes that an effective laser treatment would be a big saving in health costs, but "more work is certainly needed" to confirm that this method works, and if so to figure out why.
Chu's team suggests that the technique works because P. acnes is killed by exposure to the specific wavelengths used in this laser, whose light penetrates to just below the top layer of epidermis.