What Is Acetyl Sh-Tetrapeptide-39?
Acetyl Sh-Tetrapeptide-39 is a lab made peptide created by adding an acetyl group to the short chain of four amino acids known as Sh-Tetrapeptide-39. This small tweak helps protect the peptide, making it more stable and efficient when applied to skin. The raw materials are typically plant based or bio-synthetic amino acids that are linked together through controlled fermentation. After the peptide chain is formed, chemists attach the acetyl group, purify the mixture, then dry it into a fine powder ready for cosmetic use.
Peptides earned their place in skin care in the early 2000s when researchers showed they could signal skin to look firmer and smoother. Acetyl Sh-Tetrapeptide-39 followed soon after as brands searched for gentler options that target multiple concerns without irritation. Today the ingredient is found in lightweight serums, anti aging creams, eye treatments, sheet masks and overnight moisturizers where it works alongside hydrators and antioxidants.
Acetyl Sh-Tetrapeptide-39’s Cosmetic Benefits/Uses
This peptide is prized for one main job in beauty formulas
As a skin conditioning agent it helps skin feel softer, look more even and stay comfortably hydrated. By supporting the skin’s natural barrier it can reduce the appearance of fine lines caused by dryness and leave a smoother finish that improves how makeup sits on the face.
Who Can Use Acetyl Sh-Tetrapeptide-39
This peptide is considered gentle enough for most skin types including oily, combination, normal and dry. Its light texture and low risk of clogging pores also make it a suitable option for acne-prone skin. Those with very sensitive or compromised skin can usually tolerate it as well since it does not exfoliate or alter pH, though they may prefer formulas that pair it with soothing ingredients like panthenol.
Acetyl Sh-Tetrapeptide-39 is synthesised from plant derived or bio-identical amino acids and contains no animal by-products, so it is typically acceptable for vegans and vegetarians. Always check the full ingredient list of the finished product to confirm that other components are cruelty-free if that is a priority.
No specific warnings exist for use during pregnancy or while breastfeeding, yet research on many cosmetic peptides in these groups is limited. This information is educational only and not medical advice. Expectant or nursing mothers should show any skincare product to their healthcare provider before adding it to a routine.
The ingredient does not make skin more sensitive to sunlight and can be used morning or night without increasing the risk of sunburn. As always daily sunscreen remains important to protect overall skin health.
Potential Side Effects/Adverse Reactions
Reactions to topical Acetyl Sh-Tetrapeptide-39 differ from person to person. The points below outline potential effects that could occur, although most users will not encounter them when the ingredient is formulated and used correctly.
- Mild redness or warmth immediately after application
- Temporary itching or tingling on sensitive areas such as around the eyes
- Rare allergic contact dermatitis presenting as persistent rash or swelling
- Interaction with highly acidic or exfoliating products that may heighten irritation
If you experience any persistent discomfort stop use and consult a qualified healthcare professional for guidance.
Comedogenic Rating
Rating: 0 / 5
Acetyl Sh-Tetrapeptide-39 is a tiny, water-soluble peptide that does not contain heavy oils, waxes or fatty acids known to block pores. Because it sits lightly on the skin and is usually delivered in thin serums or lotions, the risk of pore congestion is considered negligible.
This makes the ingredient generally suitable for people who are prone to acne or breakouts.
Keep in mind the overall comedogenicity of a finished product also depends on the other ingredients in the formula and how heavily it is applied.
Summary
Acetyl Sh-Tetrapeptide-39 is a lab crafted peptide that conditions the skin by supporting its barrier so the surface feels softer looks smoother and holds moisture better. It does this through a stabilised four-amino-acid chain that signals skin to maintain a healthy balance and resist dryness induced fine lines.
While not as famous as retinol or vitamin C the peptide has carved out a quiet niche in modern serums moisturisers and eye creams thanks to its gentle profile and compatibility with most other actives.
Current data shows it is safe for daily use with a very low chance of irritation or clogged pores. As with any new skincare ingredient it is wise to patch test a product first to make sure your skin agrees with the full formula.