What Is Oligopeptide-138?
Oligopeptide-138 is a lab-crafted chain of 11 amino acids that include alanine, glutamine, isoleucine, leucine, lysine, phenylalanine, tyrosine and valine. Scientists originally explored short peptides like this one for their ability to signal skin cells to behave more youthfully, which led skincare formulators to adopt it in the early 2000s. It is produced through solid-phase peptide synthesis, a step-by-step process where each amino acid is added in a controlled sequence to build the exact peptide needed. Because it is entirely synthetic, the ingredient is free of animal by-products and can be made with high purity and consistency. You will most often spot Oligopeptide-138 in anti-aging serums, eye creams, firming lotions, sheet masks, post-procedure soothing gels and specialized moisturizers that aim to improve skin resilience and smoothness.
Oligopeptide-138’s Cosmetic Benefits/Uses
This peptide is prized for one primary role in skincare formulas.
Skin Conditioning: Oligopeptide-138 helps skin feel softer, smoother and better hydrated. By supporting the skin’s natural barrier and encouraging a well-balanced moisture level, it can leave the complexion looking plumper and more refreshed, which is why formulators often include it in products designed to minimize fine lines and improve overall skin texture.
Who Can Use Oligopeptide-138
Oligopeptide-138 is generally friendly to all skin types, including dry, oily, combination and sensitive skin, because it is lightweight, non-occlusive and formulated to support the skin barrier without heavy oils or fragrances. Extremely reactive or allergy-prone individuals should still proceed with caution, as any peptide can trigger sensitivity in rare cases.
The peptide is fully synthetic and contains no animal by-products, which makes it suitable for both vegans and vegetarians.
No specific warnings link Oligopeptide-138 to pregnancy or breastfeeding concerns, but research on topical peptides during these life stages is limited. This is not medical advice and pregnant or nursing women should show any product containing this ingredient to their doctor before use to be on the safe side.
Oligopeptide-138 does not cause photosensitivity, so it will not make skin more prone to sunburn. Standard daytime sun protection is still recommended for overall skin health.
Potential Side Effects/Adverse Reactions
Side effects and reactions to the topical application of Oligopeptide-138 can vary from person to person. The following is a list of potential side effects, and they are highly unlikely to represent the typical user experience. Assuming the ingredient has been utilized correctly by the manufacturer, most users will not experience any negative effects.
- Mild redness or flushing, especially on very sensitive skin
- Temporary itching or stinging at the application site
- Localized swelling in rare allergic responses
- Dry patches or tightness if the formula lacks adequate moisturizers
- Breakouts in individuals highly prone to peptide or preservative sensitivities
If any of these effects occur stop using the product and consult a qualified healthcare professional or dermatologist.
Comedogenic Rating
Rating: 0/5
Oligopeptide-138 is a small, water-soluble peptide with no oily or waxy components, so it does not clog pores on its own. Because it is typically used at very low concentrations and has a lightweight molecular structure, the risk of it trapping oil or debris inside follicles is minimal. For these reasons it earns a solid zero on the comedogenic scale.
This makes the ingredient generally suitable for people who are prone to acne or frequent breakouts. Keep in mind that the overall formula matters; if the peptide is blended into a rich cream full of heavy emollients, the finished product could still feel greasy or pore-clogging for some users.
Summary
Oligopeptide-138 is a lab-made chain of 11 amino acids that conditions skin by supporting its barrier, boosting surface hydration and encouraging a smoother, plumper look. It works by sending gentle signals that help skin cells maintain a healthier, more resilient state, which can soften fine lines and improve overall texture.
While not as famous as big-name peptides like Matrixyl or copper peptides, it has a steady following among formulators who want a targeted, wrinkle-smoothing boost without adding heaviness or animal-derived materials. You will mainly spot it in mid to high-end serums, eye creams and post-procedure soothing gels.
Topically applied Oligopeptide-138 is considered very safe, with low rates of irritation or allergy reported in the literature. As with any new skincare ingredient it is smart to perform a quick patch test when trying a fresh product, especially if you have sensitive or reactive skin.