Question 1

Silicone Sheeting and Gel

Accepted Answer

Silicone has been the standard in scar management since the 1980s, when surgeons caring for burn patients observed that those wearing pressure garments with silicone inserts healed with flatter, softer scars. That observation led to decades of refinement, and today silicone reaches scars in two main forms: sheets and gels.

Both work through the same general mechanism: by maintaining consistent moisture and temperature at the scar's surface, silicone appears to signal the collagen-producing cells (fibroblasts) to slow down. There's also evidence that silicone directly influences growth factors and signaling molecules (cytokines) involved in scarring, though researchers haven't pinpointed the exact mechanism.

When to Use Sheets

Silicone sheets tend to perform better in controlled clinical studies, likely because they deliver more consistent, prolonged contact with the scar. The tradeoffs are real: sheets need to be worn 12 to 24 hours a day to be effective, they can be visible under thin clothing, and they don't stick well to areas that move a lot, like joints or the face.

When to Use Gel

Silicone gels are more forgiving. They apply like a thin lotion, dry to a nearly invisible film, and work in areas where sheets simply can't stay put. The tradeoff is that gel requires reliably consistent application, and in some studies it slightly underperforms sheets used optimally.

My Recommendations

For most of my body contouring patients, I recommend sheets on tummy tuck, body lift, and breast surgery scars where they're easy to wear under clothing. For facial scars, scars near the mouth or eyes, or scars over active joints, gel is almost always the better choice. Either way, silicone needs to be used consistently for at least two to three months before you should expect to see meaningful results.

One suspicion I've had for years is that scars perform better with less friction from clothing. Tapes and silicone seem to limit this irritation. Above all, consider what's touching your scar and put something between your scar and your clothes to reduce friction.

Question 2

Corticosteroid Injections

Accepted Answer

Steroid injections remain one of my most effective tools for both hypertrophic scars and keloids. The steroids reduce inflammation and inhibit excessive collagen production. These injections need to be spaced appropriately—typically four to six weeks apart—and usually require multiple sessions.

Question 3

5-Fluorouracil (5-FU): A Different Approach to Scar Treatment

Accepted Answer

5-Fluorouracil has an interesting backstory in scar treatment. Researchers originally developed it in the 1950s as a chemotherapy drug for colorectal and breast cancer, and for decades nobody thought of it as anything else. In the 1990s, dermatologists who were injecting it into skin cancers noticed something unexpected: the scars left behind were flatter and softer than anyone predicted. Richard Fitzpatrick's 1999 paper established 5-FU as a legitimate option for hypertrophic scars and keloids, and since then it has earned a real place in the scar treatment toolkit—though it remains astonishingly underused.

How 5-FU Works

The mechanism is worth understanding. 5-FU is what scientists call a pyrimidine analog—it mimics a normal building block of DNA and slips into its place during cell replication, effectively stopping the process. In a keloid or hypertrophic scar, the collagen-producing cells (fibroblasts) cranking out all that excessive collagen are among the most rapidly dividing cells in the scar, so the drug hits them harder than the surrounding tissue. The result is less collagen production, fewer overactive fibroblasts, and gradual flattening of the scar.

Why I Often Choose 5-FU Over Steroids Alone

What I appreciate about 5-FU is that it sidesteps some of the problems that can appear with repeated steroid injections, particularly skin thinning (atrophy), broken blood vessels, and color loss around the scar. It's actually my first choice when I'm concerned about the cosmetic side effects of steroids, because 5-FU gives me another effective option that works through a completely different pathway.

Question 4

Combining 5-FU with Steroid Injections (Triamcinolone)

Accepted Answer

The combination of 5-FU with triamcinolone (a corticosteroid) has become one of the more powerful approaches I use for stubborn keloids and hypertrophic scars. I think of them as complementary agents attacking the same problem from different angles.

Why the Combination Works

Triamcinolone works on the inflammatory side of scarring, calming down the signaling that drives fibroblasts into overdrive. 5-FU works on the fibroblasts themselves, directly inhibiting their ability to replicate and produce collagen. Using them together tends to produce better results than either one alone, and clinical research supports this. Darougheh's 2009 trial compared triamcinolone by itself against triamcinolone mixed with 5-FU and found the combination produced better scar flattening, less itching and pain, and fewer patients needed to stop treatment because of side effects. Subsequent analyses of the broader research have reached similar conclusions.

How I Use This Combination

The practical reason this combination matters so much is dosing. Adding 5-FU lets me use less steroid overall and still get a better result. The typical mix I use is about 9 parts 5-FU to 1 part triamcinolone, injected every 6 to 8 weeks for several sessions depending on how the scar responds. For scars that have frustrated patients through earlier treatment attempts, this combination has produced some of the most satisfying results I see in my practice.

Question 5

Laser Therapy

Accepted Answer

Laser therapy has evolved significantly over the years. Different lasers target different aspects of scar tissue: some reduce redness by targeting blood vessels, others soften and flatten the scar by creating microscopic channels that trigger remodeling. I often use fractional lasers for scars that restrict movement or haven't responded well to other treatments.

Question 6

Physical (Mineral) Sunscreens

Accepted Answer

Physical sunscreens use zinc oxide and titanium dioxide to sit on top of the skin and physically reflect and scatter UV radiation. They start working the moment you apply them, they aren't absorbed into the body in any significant amount, and they're currently the only two sunscreen active ingredients the FDA recognizes as Generally Recognized As Safe and Effective (GRASE).

Question 7

Chemical Sunscreens

Accepted Answer

Chemical sunscreens—including avobenzone, oxybenzone, octinoxate, and octisalate—absorb UV radiation and release it as heat. That process can produce cell-damaging molecules (reactive oxygen species) as a byproduct, and Hanson and colleagues demonstrated in 2006 that once several common chemical filters penetrate past the skin's outermost layer (the stratum corneum), they actually increase free radical generation in the deeper skin compared to untreated skin.

On intact, mature skin the barrier keeps most of the filter on the surface where it's doing its job, and the net benefit of using any sunscreen consistently vastly outweighs this concern for the general population—though I conceptually disagree and prefer reflecting UV rays to allowing them to interact with the skin.

Question 8

Why This Matters for Healing Scars

Accepted Answer

Healing scar tissue is a different environment. Inflammation is already driving the remodeling we're trying to calm down, and free radicals feed directly into some of the same pathways that fuel abnormal scarring. Chemical filters also cause contact irritation (dermatitis) and sun-triggered allergic reactions (photoallergic reactions) more often than mineral ones, and researchers have recently shown that several active ingredients reach measurable blood levels that the FDA has asked manufacturers to study further.

For those reasons, I always recommend physical sunscreen on healing surgical scars. Zinc oxide has the added benefit of mild anti-inflammatory properties, which can help a scar that's still maturing. I always tell patients that year-round sun protection over any scar—or for that matter any skin they care about—remains a lifelong habit worth keeping.

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