Kiehl’s is stepping into one of skin care’s most pressing new categories with Power Plump 1CC CollaShot Serum ($55), a gel-to-serum treatment formulated specifically for the volume loss that comes with GLP-1 medications. The brand is calling it plumping “without the needle,” claiming a visible surface effect equivalent to 1cc of hyaluronic acid filler.
The formula centers on the brand’s proprietary Pink RHC Collagen alongside vitamin B12 and a collagen-supporting active blend of Rhamnose and Proxylane. Kiehl’s Supra-Liposome technology is meant to “push” absorption further than traditional collagen serums, and the B12 complex gives the jelly-textured formula its signature pink tint. The brand recommends using it twice daily.
What sets this launch apart is the GLP-1-specific testing behind it. Kiehl’s ran clinical trials across 16 skin-aging attributes in GLP-1 users specifically, reporting a 22 percent improvement in cheek elasticity after eight weeks. At the four-week mark, 94 percent of GLP-1 users in testing agreed the serum addressed skin concerns tied to their weight-loss journey, 92 percent said skin looked firmer, and 91 percent said it looked plumper.
It’s a direct response to a skin concern dermatologists have been fielding more of as GLP-1 use has climbed. “Patients on GLP-1 medications experience fat loss to varying degrees, and because cheek volume depends on both fat and collagen, that loss can make the face look flatter or more deflated faster than typical aging alone,” says New York dermatologist Jane Yoo, MD. “I recommend a serum like this as part of a proactive collagen strategy to support the skin’s structural health during weight loss and as a maintenance step alongside in-office procedures. It won’t replace injectables, but it helps the skin stay resilient through the changes GLP-1 patients are experiencing.”
New York dermatologist Dendy Engelman, MD sees the same pattern in her own patients. “As facial fat diminishes, patients often notice their skin appears thinner, less resilient and less able to ‘bounce back’ because the underlying collagen network is under greater mechanical stress,” she says. What sets this formula apart from the crowd, in her view, is what it’s built around. “Most plumping serums lean on hyaluronic acid or glycerin to pull in water and create a temporary filling effect. This formula is signaling toward the skin’s own collagen production pathway, using a biotech-derived polypeptide rather than a traditional marine or bovine-sourced collagen, which tends to sit on the surface rather than communicate with skin cells.” She points to the vitamin B12 as a tell that the formulation wasn’t chasing a trend: “It’s not an ingredient I’d expect in a plumping serum, and it suggests real formulation intent.”
What is especially impressive about the formula, according to Dr. Yoo, is the recombinant human collagen at its core. “Kiehl’s is among the first brands to bring this technology to the U.S. market,” she says. “Unlike traditional collagen serums, which use large protein molecules that mostly sit on the skin’s surface, recombinant collagen peptides are smaller and more soluble, so they penetrate better and actually support the skin’s own collagen-producing environment.” She adds that staying power matters as much as the science. “Clinically, I look for formulas patients will actually stick with, since collagen support takes months, not days. This serum delivers visible firmness and plumpness without irritation.”
Dr. Engelman makes a similar point about how the serum fits into a broader GLP-1 skin-care routine. “While no topical product can restore the structural volume that’s been lost, I encourage these patients to adopt a collagen-supportive skin-care routine alongside in-office treatments when appropriate,” she says. “This should be thought of as part of a comprehensive strategy: lifestyle measures that support skin health, daily sunscreen, collagen-supportive skin care, and, when indicated, biostimulatory injectables or energy-based devices to address deeper collagen loss.”
Power Plump 1CC CollaShot Serum hits the Sephora app July 27 and Kiehls.com August 1.
