Stretch marks are best to treat while they are red. Lasers are quite good at removing the redness and IMPROVING the texture of stretch marks. It’s extremely difficult to completely erase stretch marks, although significantly improving red ones is quite achievable using modern, pulsed-dye or KTP lasers. Once stretch marks lose their red color, laser treatments offer much less improvement. During this phase, the non-ablative fractionated lasers, such as the Fraxel Dual, are often used, with much less improvement than is seen when treating red stretch marks.
Stretch marks result from damage to elastic fibers in the skin, often due to hormonal changes such as pregnancy, birth control pill use, taking oral steroids, or aggressive use of topical steroid creams in a given area. Most people attribute stretch marks to physical factors such as weight gain, increasing muscle mass from weight lifting, or physical activity that causes the elastic fibers in the skin to stretch and break; however, it is more often the hormonal changes that accompany weight gain or changes in body architecture that lead to the stretch marks. Restoring elastic fibers to skin once they are damaged or lost is a very difficult thing to do. Agents that repair sun-damaged skin offer some help to improving the appearance of stretch marks, since sun also damages elastic fibers, but in a different way. Retin-A (and its relatives) and AHAs (like ammonium lactate or glycolic acid) improve stretch marks very gradually over time.