AmLactin works through lactic acid, an alpha hydroxy acid (AHA) that both exfoliates dead skin cells and pulls moisture into the skin. This dual action is what makes it effective for rough, dry, or bumpy skin. The lactic acid loosens the “glue” holding dead cells together on the skin’s surface while simultaneously acting as a natural humectant, binding water to keep skin hydrated.
How Lactic Acid Exfoliates
Your skin’s outermost layer, the stratum corneum, is made up of flat, dead skin cells held together by protein structures called desmosomes. Think of desmosomes as tiny rivets connecting cells to each other. When skin is rough or flaky, those dead cells are building up faster than they’re shedding.
Lactic acid penetrates this outer layer and breaks apart those intercellular bonds. Once the connections dissolve, dead cells release from the surface and shed. This process, called desquamation, reveals the smoother, newer skin underneath and speeds up the rate at which your skin naturally turns over. The result is less flaking, less roughness, and a more even texture over time.
Why It Hydrates, Not Just Exfoliates
Lactic acid isn’t just a chemical peel in lotion form. It’s actually a component of your skin’s natural moisturizing factor (NMF), a collection of compounds including amino acids, urea, and lactate that exist naturally in healthy skin. These NMF components are highly efficient humectants, meaning they attract water molecules from the surrounding environment and bind them into the skin’s outer cells.
When you apply AmLactin, the lactic acid supplements this natural system. It draws moisture into the stratum corneum and helps it stay there. There’s also evidence that lactic acid stimulates the production of ceramides, the lipid molecules that form the skin’s moisture barrier. So it’s doing two things at once: clearing away the dead layer that makes skin feel rough, and reinforcing the barrier that keeps skin hydrated underneath.
The Role of pH
For lactic acid to work properly, the product needs to sit at the right pH. AmLactin’s formulas are stabilized between pH 5.0 and 5.5, which is close to the skin’s own natural acidity. This matters because AHAs are most active at lower pH levels, but going too low causes irritation and barrier damage. The 5.0 to 5.5 range lets the lactic acid dissolve dead cell bonds effectively while staying gentle enough for regular use without triggering inflammation.
Lactic Acid Concentrations Across Products
Not all AmLactin products are the same strength. The Daily Nourish Lotion contains 12% lactic acid, which is the standard concentration for general dry skin maintenance. The Ultra Smoothing Cream steps up to 15% lactic acid, designed for thicker, more stubborn rough patches. Higher concentrations exfoliate more aggressively, so the 15% formula is typically better suited for areas like elbows, knees, and feet rather than thinner skin.
How It Treats Keratosis Pilaris
AmLactin is one of the most commonly recommended over-the-counter treatments for keratosis pilaris, the condition that causes small, rough bumps often described as “chicken skin.” These bumps form when plugs of dead skin cells build up around individual hair follicles, trapping the hair and creating that sandpapery texture. The bumps are harmless but persistent.
Lactic acid addresses the root cause by dissolving the keratin plugs that block the follicles. With consistent use, the dead cell buildup clears and the bumps flatten. It won’t cure keratosis pilaris permanently since the skin’s tendency to overproduce keratin remains, but regular application keeps the plugs from reforming. Pediatric and dermatology guidelines specifically recommend lactic acid lotions like AmLactin for this condition in older children and adults.
What to Expect When You Use It
The most common side effects are mild burning, stinging, or redness where you apply it. This is especially likely if you use it on skin that has any cuts, scrapes, cracks, or freshly shaved areas. A slight sting on compromised skin is normal and usually fades quickly. If your skin gets progressively more irritated or your condition worsens instead of improving, that’s a sign to stop using it.
Facial skin deserves extra caution. The skin on your face is thinner and more reactive, and AmLactin can cause noticeable redness and irritation there. Most formulations are designed for the body rather than the face.
Sun Sensitivity Is Real
Because lactic acid is an AHA, it increases your skin’s sensitivity to ultraviolet radiation. The FDA has reviewed evidence showing that topically applied AHAs make skin more vulnerable to sunburn during the period you’re using them and for up to a week after you stop. This isn’t a minor footnote. The FDA recommends that anyone using AHA-containing products use sunscreen, wear protective clothing, and limit sun exposure both during use and for a week after discontinuing. If you’re applying AmLactin to sun-exposed areas like your arms or legs during warmer months, sunscreen becomes especially important.