What Is It?
Lasers are a treatment option performed in a doctor’s office aimed at preventing light-to-moderate acne, although it has shown some promise in the treatment of severe acne (cysts/nodules).1Laser therapy tends to work better and have fewer side effects on lighter skin tones, and works by concentrating light, which penetrates the skin. Much like at-home light devices, lasers work primarily on the premise of exciting compounds that bacteria produce called porphyrins.2When the laser light excites the porphyrins, this damages the bacterial wall, effectively killing the bacteria.3Fewer acne bacteria should help reduce symptoms of acne. Laser treatment may also reduce sebum (skin oil) levels. Lower sebum levels are associated with lower incidence and severity of acne. Lastly, lasers may have anti-inflammatory properties. Since acne is at its root an inflammatory disease, reducing inflammation can help reduce acne as well.1Laser treatment normally requires three treatments, about a month apart, at the doctor's office, and costs $200-$500 per treatment, or $600-$1500 total. Doctors sometimes recommend more treatments and/or more frequent treatments, depending on the doctor’s opinion and the severity of acne. Results are incomplete and temporary, and thus laser treatment is not amongst the most popular treatments prescribed.
Types of Lasers
Doctors use various types of lasers for the treatment of acne. They are characterized based on the color and wavelength of light that they emit. Generally speaking, the different types of light penetrate more or less deeply into the skin. There are 3 types: (1) pulsed-dye lasers (PDL), (2) potassium titanyl phosphate lasers (KTP), and (3) infrared lasers. All PDL lasers emit yellow 585-595nm light, and all KTP lasers emit green 532nm light. Infrared lasers come in different types, each of which emits a different colorless wavelength above 1000nm. Infrared lasers include the 1450nm diode (1450nm), erbium:glass (1550nm or 1540nm) and Nd:YAG (1064nm and 1320nm) lasers.1Most lasers used in the treatment of acne are called fractional lasers, for instance the Fraxel® laser. These lasers point light at very small columns of skin, and therefore produce fewer side effects than lasers that shine light on larger areas of the skin. In the last few years, a new infrared “vacuum” laser called Isolaz® has also become available.4-6This laser uses a vacuum to isolate and “suck up” a small area of the skin on which laser light is then applied.5There is also a kind of PDL laser, which uses not only light but also heat, called the pulsed light and heat laser. Generally speaking, infrared lasers penetrate the skin more deeply than other lasers7, followed by PDL, and finally KTP, although the depth to which a laser can penetrate also depends on the darkness of the skin. Darker skin prevents the light from penetrating as far.7-8
Does It Work?
Scientists have produced several studies attempting to gauge the effectiveness of lasers for acne. However, these studies are almost all small cohort (just a few people), sometimes lack split-face design (comparing one side of the face to the other), tend to lack long (follow-up so it is hard to tell if results last), rely on patient reports of acne severity (which is subjective), and often employ no controls (so there is nothing to compare results against). Regardless, almost all of the studies show at least some improvement in acne symptoms, with results ranging from 36% to 83% clearance.1,9-21Consensus amongst researchers is that results of laser treatment are temporary, since colonies of acne bacteria grow back quickly. Results are also incomplete, meaning lasers alone usually do not completely clear acne.9However, scientists are studying newer lasers in an attempt to increase effectiveness, reduce side effects, and extend treatment results for longer periods of time.
Lasers can also be used alongside other treatments. One study that compared the results of laser treatment in combination with salicylic acid treatment showed that using the laser treatment in addition to salicylic acid treatment resulted in a better improvement in acne than salicylic acid alone.15This result suggests that laser treatment may be beneficial if used in combination with other treatments.15
Light therapy options that are not laser-based: Doctors have various light therapy options available to their patients such as intense pulsed light (IPL) treatment, which uses flash lamps to generate high intensity light that is not as concentrated as laser light, as well as LED light treatment. Overall, the concentrated light used in laser treatment has been shown to be more effective in treating acne than other light therapy options, including IPL or LED.1One exception may be photodynamic therapy (PDT), which involves first applying a topical photosensitizing agent and then shining light on the sensitized skin, and tends to produce better results than other light therapy options.
Most of the side effects of laser therapy are transient and mild. Some patients experience pain or discomfort during treatment. Patients report varying levels of redness after treatment, as well as some inflammation and skin peeling and sometimes blistering and/or crusting.1,22The severity of these side effects varies based on the type of laser used. The deeper a laser penetrates the more severe the side effects tend to be. For example, infrared lasers 1450 diode can cause considerable pain that requires the use of a topical anesthetic.1However, with the use of a topical anesthetic, pain is well tolerated.1,20KTP and PDL lasers can cause bruising, which usually goes away within ten days. KTP and PDL lasers can also cause some temporary darkening of the skin, especially in people with darker skin who have exposed themselves to the sun prior to the procedure.20
At this time, laser therapy is not considered a “first line treatment,” meaning it is best to try other, more effective and reliable treatments first. It is also difficult to discern from the data we currently have available which lasers are best.
A 2008 systematic review of the 19 available controlled studies on lasers and acne, published in The Journal of the European Academy of Dermatology and Venereology, concluded: ” ...most of the studies were of suboptimal methodological quality...we conclude that [light] treatments with lasers...possess the potential to improve inflammatory acne on a short-term basis...[however] [light] treatments for acne today are not included among first-line treatments.”11