Peptides are on more and more serum labels, and lately they are in the news for the wrong reasons. Here is what peptides in skincare are, what the research does and doesn't show, how they differ from the peptide products the TGA has warned about, and how to use one.
What are peptides in skincare?
Peptides are short chains of amino acids, the building blocks of proteins. TGA — Unapproved peptide products
Some skincare peptides are made in a lab; others come from breaking down larger proteins, such as collagen or keratin. Schagen 2017 — peptide review Nukaly 2026 — systematic review
Their names describe the chemistry. In palmitoyl tripeptide, for example, "tri" means three amino acids (a hexapeptide has six), and "palmitoyl" means a fatty acid has been attached, which can help a peptide get past the skin's surface. Schagen 2017
What do peptides do for skin?
Less is known than you might expect. A 2017 review found little research in people: some studies were very small, many were not published in scientific journals, and some tested a peptide alongside other active ingredients, so its own effect was unclear. Schagen 2017
A 2026 systematic review found 19 randomised trials comparing peptides with a placebo, but only two small ones tested peptides on the skin; the rest were supplements, mostly collagen. Its authors say the evidence is too limited for firm conclusions. Nukaly 2026
So a peptide serum may help skin look smoother or firmer, but no one can say how much. A study of one peptide also tells you little about a different peptide, a different amount or a whole product. Schagen 2017 Nukaly 2026
Are peptides safe?
It depends on the product. In Australia, cosmetics go on the outside of the body to change how it looks, clean it, keep it in good condition or protect it. An injected product can't be a cosmetic, and products swallowed to improve how skin looks are regulated as therapeutic goods, like medicines. TGA — Cosmetics or therapeutic goods (PDF)
The TGA has warned about unapproved peptide products, often injections promoted online for weight loss, muscle growth, anti-ageing and performance. They haven't been assessed for safety, quality or effectiveness, labels may not match the contents, and injecting them risks contamination and infection. Reported problems include severe allergic reactions needing hospital care. A "research use only" label doesn't make them legal to sell. TGA — Unapproved peptide products A GP quoted by the RACGP warns there is no reliable way to know what is in the vial, whether the dose is accurate or whether it is sterile. RACGP newsGP
Peptide serums sold as cosmetics are different: they go on the skin, and peptides were well tolerated in the 2026 review's trials. Nukaly 2026 Any skincare can still irritate or cause an allergy; fragrances and other cosmetic ingredients are possible triggers. healthdirect — Contact dermatitis
How do I use a peptide serum?
Use it like any other serum, following our skincare routine guide.
- Try it on a small area first, and introduce one new product at a time. DermNet — Sensitive skin
- Give it time: the trials ran for four to twelve weeks, so a few days is too soon to judge. Nukaly 2026
- Stop using any product that gives you an itchy red rash. healthdirect — Contact dermatitis
- A serum is not a sunscreen. Cancer Council recommends a broad-spectrum, water-resistant SPF 50 or 50+ sunscreen every day the UV index is forecast to reach 3 or above. Cancer Council
When to see your GP or dermatologist
See your GP if:
- a rash blisters, swells, spreads beyond where you applied a product or isn't getting better, or comes with a fever or feeling unwell healthdirect — Contact dermatitis
- you notice a new spot, a crusty sore that isn't getting better, or a mole or freckle changing in colour, size, shape or thickness healthdirect — Skin cancer checks
- you have side effects from a peptide injection or other unapproved peptide product (you can also report it to the TGA) TGA RACGP newsGP
Our pigmentation guide explains which changes in skin colour need a medical check first.
What can we talk about at Melbourne Wellness?
At an advanced skin analysis appointment we can look at your skin with you, go through your routine and talk about whether a peptide serum is worth adding. If anything needs a medical opinion, we will say so.
Questions you might bring:
- What would a peptide serum add to my routine?
- Do any of my products already contain peptides?
- Which sunscreen suits my skin?
Several Osmosis products in our shop contain peptides. Affirm MD, the MD-range serum for the face and neck (our Affirm MD post), has three (skin consultation recommended); it contains almond and macadamia-derived ingredients, so check its ingredient list if you have a nut allergy. Allergy & Anaphylaxis Australia The retinal (vitamin A) serums Calm, Correct and Renew MD have one to three each (Renew MD: skin consultation recommended); see how the three compare. Replenish, the antioxidant serum, and the Boost mist (which mist suits you) have one each. None of the studies above tested these products. Prescription vitamin A creams such as tretinoin should not be used in pregnancy, and MotherSafe's factsheet does not mention retinal, so if you are pregnant, breastfeeding or planning a pregnancy, check with your doctor, pharmacist or MotherSafe before starting a retinal serum. MotherSafe (PDF)
See also vitamin C and skin.
