Key takeaways:
Glycyl-L-histidyl-L-lysine copper (GHK-Cu) is used in some skin care products. It may help moisturize skin and reduce fine lines.
Compounded GHK-Cu creams aren’t FDA-approved to treat wounds or help with hair growth.
GHK-Cu injections aren’t FDA-approved to treat any medical condition. Products labeled “research use only” aren’t made for use in people.
Glycyl-L-histidyl-L-lysine copper (GHK-Cu) is getting a lot of attention for its possible benefits for skin, hair, and wound healing. This copper peptide is already found in many skin care products. Now, compounded creams and injections are also entering the market.
But the excitement around GHK-Cu has moved faster than the research. Small human studies have looked at some skin benefits. But many claims are based only on lab or animal studies. Even less is known about the safety and benefits of GHK-Cu injections. Here’s what the research says so far and what you should know before trying GHK-Cu.
What is GHK-Cu?
Researchers first discovered the compound GHK in 1973. Since then, GHK-Cu has been added to cosmetic skin care products and compounded topical products. More recently, compounded GHK-Cu injections have become available.
GHK-Cu stands for glycyl-L-histidyl-L-lysine copper. GHK-Cu occurs naturally in your body and is found in blood, saliva, and urine. Your body also releases it after an injury because it helps with wound healing and tissue repair.
GHK-Cu helps carry copper to cells. Copper helps your body make collagen and elastin and grow new blood vessels. GHK-Cu may also help control inflammation and protect cells from damage.
But the fact that GHK-Cu occurs naturally in your body doesn’t mean that GHK-Cu creams or injections are automatically safe.
What are the potential benefits of GHK-Cu?
There’s a lot of interest in what GHK-Cu might be able to do. In lab studies, it helps the body make collagen and elastin, which keep skin healthy and strong. That sounds promising, but results from cell or animal studies don’t always translate to people. Here’s where the research stands for some of the most popular uses.
Skin health
Skin care is where most of the human research on GHK-Cu is available. In two small studies, Cosmetic creams with GHK-Cu helped improve skin thickness and reduce the appearance of fine lines and wrinkles.
But the research is still limited. Most of the available research comes from lab or animal studies. GHK-Cu creams may help with age-related skin changes, but larger studies in people are needed to know how well they really work. There aren’t any strong human studies on how injectable GHK-Cu affects skin health.
Wound healing
There’s a reason researchers are interested in GHK-Cu for wounds. In lab and animal studies, it helped with collagen production, new blood vessel growth, and inflammation.
But we don’t yet have evidence showing that topical or injectable GHK-Cu helps wounds heal in people, like diabetic ulcers, pressure injuries, or other open wounds.
Hair growth
You may also see GHK-Cu promoted for thicker hair or hair regrowth. But there’s very little evidence from human studies to support these claims.
GHK-Cu has shown hair growth effects in mice. But there aren’t any strong human trials showing that it treats hair loss. It isn’t known whether GHK-Cu creams or injections actually help people regrow hair. We also don’t know whether it works better than proven hair growth treatments.
Joint and muscle health
Injectable GHK-Cu is marketed for joint pain, muscle growth, injury recovery, and general wellness.
But human studies haven’t tested GHK-Cu injections for these uses. There’s no evidence that GHK-Cu builds muscle. And there’s no solid evidence that injecting it relieves joint pain or helps injuries heal.
What are the side effects of GHK-Cu?
The full range of GHK-Cu side effects isn’t clear. There hasn’t been enough research in people to know all its possible side effects or how often they occur.
Reports online about side effects can give clues, but they can’t tell us how often a problem happens or prove that GHK-Cu caused it.
Possible risks include:
Skin irritation: Topical GHK-Cu may cause redness, itching, burning, or irritation where you apply it. Stronger compounded products could have different risks than lower-strength cosmetics.
Injection reactions: GHK-Cu injections may cause pain, redness, swelling, or irritation at the injection site.
Infection: Bacteria or fungi can get into vials during production or handling if the right safety standards aren’t followed. Injecting contaminated products can cause skin infections or serious bloodstream infections.
Immune reactions: Injected peptides can sometimes trigger an immune response. These responses can be serious and life-threatening.
Copper toxicity: Injecting GHK-Cu adds copper directly to your body. Too much copper can build up in your organs and cause damage. We don’t know what dose of injectable GHK-Cu could lead to copper toxicity.
Joint damage: Early research suggests that too much copper may damage cartilage cells.
Is GHK-Cu FDA-approved?
No. GHK-Cu isn’t FDA-approved to treat age-related skin changes, wounds, hair loss, joint pain, or any other health condition.
Despite this, you may still find GHK-Cu products available for purchase. Regulations on GHK-CU products depend on how they’re made and used:
Cosmetic GHK-Cu: GHK-Cu can be added to skin care products meant to moisturize your skin or improve its appearance. Cosmetics don’t need FDA approval or clearance before they’re sold. Companies are responsible for making sure their products are safe and labeled correctly.
Compounded topical GHK-Cu: As of May 2026, noninjectable GHK-Cu is currently on the FDA’s 503A Bulk Drug Substances List under Category 1. This means the FDA is still deciding whether pharmacies should be allowed to use it to make compounded medications. Category 1 status gives pharmacies some temporary protection to make and dispense topical GHK-Cu. But it doesn’t mean the product is FDA-approved or that the FDA has found it safe or effective.
Compounded GHK-Cu injections: Injectable GHK-Cu isn’t included on the FDA’s 503A Bulk Drug Substances list. The FDA advisory committee plans to meet before the end of February 2027 to discuss whether to recommend adding it to the list. This list identifies substances that traditional compounding pharmacies may use under certain conditions. Adding GHK-CU injections to the list could make it easier for people to access them. But it doesn’t mean they’re FDA-approved. GHK-Cu injections sold online are usually labeled “research use only.” These products aren’t made for use by people.
Is GHK-Cu safe?
GHK-Cu safety depends on the type of product:
Cosmetic GHK-Cu: Low-strength GHK-Cu used in cosmetics has the most reassuring safety history. In 2014, the Cosmetic Ingredient Review Expert Panel found copper tripeptide-1 to be safe for the uses and amounts it reviewed.
Compounded topical GHK-Cu: Compounded medications don’t go through the same FDA testing and approval process as prescription medications. The FDA doesn’t check each finished product to make sure it has the right concentration or is free of impurities before it reaches you. Problems with the concentration, purity, and quality of compounded medications have happened in the past. It’s not clear if compounded topical GHK-Cu is safe to use.
Compounded GHK-Cu injections: There isn’t solid human data to know what dose is safe or what can happen with short- or long-term use. Products you can purchase are typically intended for research purposes only. This means they aren’t made for use by people. There aren’t any quality standards that can assure you that these products contain the amount of GHK-Cu on the label. There’s also no way to know for sure if GHK-Cu injections are pure or sterile enough to inject.
The bottom line
There’s some early evidence that GHK-Cu may help when used in cosmetic skin care products. But there’s much less evidence to support compounded creams and injections. If you’re considering GHK-Cu for a health problem, talk with your healthcare team about your options. Avoid injecting products labeled “research use only.”
Why trust our experts?
References
Johnson, W. Jr, et al. (2018). Safety assessment of tripeptide-1, hexapeptide-12, their metal salts and fatty acyl derivatives, and palmitoyl tetrapeptide-7 as used in cosmetics. International Journal of Toxicology.
Lee, S., et al. (2023). In situ photo-crosslinkable hyaluronic acid-based hydrogel embedded with GHK peptide nanofibers for bioactive wound healing. Acta Biomaterialia.
Mayfield, C. K., et al. (2026). Injectable peptide therapy: A primer for orthopaedic and sports medicine physicians. The American Journal of Sports Medicine.
Mendias, C. L., et al. (2026). Safety and efficacy of approved and unapproved peptide therapies for musculoskeletal injuries and athletic performance. Sports Medicine.
Mokhtar, J., et al. (2026). The regenerative potential of GHK-Cu in aesthetic medicine. Aesthetic Surgery Journal.
Mortazavi, S. M., et al. (2024). Topically applied GHK as an anti-wrinkle peptide: Advantages, problems and prospective. BioImpacts.
Pickart, L. (2008). The human tri-peptide GHK and tissue remodeling. Journal of Biomaterials Science, Polymer Edition.
Pickart, L., et al. (2012). The human tripeptide GHK-Cu in prevention of oxidative stress and degenerative conditions of aging: Implications for cognitive health. Oxidative Medicine and Cellular Longevity.
Royer, A., et al. (2023). Copper toxicity. StatPearls.
U.S. Food and Drug Administration. (2026). Meeting of the pharmacy compounding advisory committee.
U.S. Food and Drug Administration. (2024).Pharmacy compounding advisory committee: FDA immunogenicity risk of compounded peptides.
U.S. Food and Drug Administration. (2026). Bulk drug substances nominated for use in compounding under section 503A of the federal food, drug, and cosmetic act.
