Time may heal all wounds, but the scars that remain can be unsightly, itchy, stiff and painful. Pharmacy aisles beckon with "clinically proven, doctor-recommended" scar products, and the Internet teems with anecdotes of different creams and elixirs that supposedly erase old scars or prevent new ones from forming.
But not all of those claims stick. "There are a thousand wives' tales and a whole bunch of things you can buy, but none have scientific validity to speak of," says Dr. Terence Davidson, a professor of surgery at UC San Diego School of Medicine.
The remedies are popular, and no wonder: Scars take six months to two years to heal, Davidson adds, and "people want to do something rather than just sit there and watch." Options include onion extract gels, vitamin oils and creams, silicone gels and antibiotic ointments. There are also sticky silicone gel sheets.
Since the products are used for months, any of these approaches can run up a hefty bill not covered by insurance. Mederma, which contains onion extract, costs $30 for a 1.76-ounce tube. A half-ounce of Kelo-cote silicone gel costs $44, and silicone gel sheets start at $25 for small sizes.
But of course, if a scar gets better after months of applying a remedy, it's hard to know whether the treatment or just time made the difference.
Very few well-designed studies have tried to answer that question, says Dr. Joseph Sobanko, a dermatological surgeon at the University of Pennsylvania Health System in Philadelphia. Because everyone heals differently, a good study compares treatments on two similar scars on the same person, such as after breast reduction, or on two halves of the same scar.
Even then, a study may report effectiveness for some esoteric measurement such as elasticity but the treatment may still leave a cosmetically unacceptable scar. "What patients and we physicians care about is whether there's a significant decrease in scar volume and whether it looks better aesthetically," Sobanko says.
The only thing really shown to help the healing process and minimize scarring, he says, is keeping a wound moist and covered. Most scar products do that. But there's little evidence that they work any better than inexpensive petroleum jelly.
A 2009 study in the Journal of the American Academy of Dermatology by Sobanko's colleagues at the University of Pennsylvania found a huge gap between the advertised benefits of over-the-counter scar products and the clinical evidence that they actually work.
For example, Merz Pharmaceuticals, which makes the popular product Mederma, says it is "clinically proven to improve the softness, texture and overall appearance of scars." But there were just two randomized comparison trials of Mederma, with a combined total of 38 participants. Neither trial found that Mederma improved the appearance of scars more than petroleum jelly.
Vitamin E oil didn't fare any better. "If it helps," says Kenneth Arndt, a dermatologist in Newton, Mass., "it's not the E but the oil." He notes that it often causes skin irritation.
Several articles in a March supplement of the Journal of the American Academy of Dermatology show that antibiotic ointments do not aid in healing or reduce the risk of infection -- but they do raise the risk of antibiotic resistance.
Silicone gel sheeting seems to be the exception. Several articles reviewing 30 years of research suggest that it can speed healing and lead to thinner, softer, less red and less painful scars. It's not clear what silicone itself does. But the sheets do a better job of keeping the scar covered, and that prevents water from evaporating from the skin.
Moisture is key because it lets the skin grow back evenly, says Dr. Jennifer Wu, a Los Angeles dermatologist. "If you slice a finger open as you're cutting your bagel in the morning, you have two edges of the wound. The new skin grows across that gap," she explains. "If the wound dries, a scab forms between the two edges. Now the skin has to grow down and across, like it encountered a boulder. It's likely to lead to a depressed, pitted scar."
Raised scars, she adds, occur when collagen fibers that usually grow parallel to the surface of the skin grow back in tangled clumps and are no longer smooth. If the growth is too exuberant or poorly organized, the result can be a large scar extending beyond the boundary of the wound. Again, keeping a wound moist helps, according to a 2010 review article in the journal Aesthetic Plastic Surgery, because it reduces production of this excess collagen.
Since the early 1980s, when silicone gel sheets were introduced for burn victims, numerous small studies have shown that the sheets reduce the risk of developing scars. They can also soften and increase the elasticity of existing scars.
But these sheets are uncomfortable and hard to apply to contoured areas, and many people won't wear them on their faces, says Dr. Thomas Mustoe, a plastic surgeon at Northwestern University's Feinberg School of Medicine in Chicago. Silicone gel is easier to use, and it dries clear on the skin. It can even be worn under makeup. "It's not as well studied, but it's increasingly recognized that silicone gel can help too," Mustoe says. "It has a moderate effect. It's not dramatic."
For large raised scars, the recommendation from a 2002 expert panel report is to inject them with corticosteroids. "Scars get red, swollen and itchy because of inflammation, and corticosteroids are anti-inflammatory. They break down scar tissue to soften bumpy scars," Wu says. Patients may need monthly shots, at $100 to $200 per office visit.
Arndt says several newer treatments for difficult scars are becoming more widespread. These include injections of the chemotherapy agent 5-flourouracil, which interferes with cell growth in the scar tissue. Also, lasers can reduce raised scars and minimize redness.
When all else fails, plastic surgeons can perform scar revision, cutting out a raised scar and carefully suturing the skin -- a tricky business that doesn't always work in people prone to large scars.
(BEGIN TEXT OF INFOBOX)
How to help prevent scars
Besides treating scars with ointments and gels, try preventing them. Here are tips from dermatologists and plastic surgeons:
One to two weeks before surgery, stop taking anything not medically necessary that thins the blood and increases bleeding. Increased bleeding leads to more bruising and swelling, and makes the scar larger. This list includes aspirin, ibuprofen, vitamin E, fish oil, garlic, ginger, ginkgo and alcohol.
Stop smoking, because smoking decreases the circulation to the skin that aids healing.
The skin on the knees, elbows and extremities gets stretched many times a day. To prevent scars from widening, use a product like Steri-strips or splints to reduce the pulling of the skin in these areas.
Exercise that gets the heart pounding can speed healing, but be sure not to strain the wound for two weeks.
Sun exposure can darken or redden the new skin permanently, leaving a more visible scar. Protect it with sunscreen or zinc oxide.
If you tend to get large, raised scars, you could get them on your earlobes when getting your ears pierced. Use pressure earrings (available online for about $45) after getting your ears pierced to reduce this risk.
Massaging along the length of a scar several times a day may help soften it and reduce its volume.
-- Cathryn Delude