Ingredient review
Acetylsalicyloyl Pentapeptide-33
INCI: Acetylsalicyloyl Pentapeptide-33
A lab-made peptide that may help firm skin and soften lines, but human studies are limited so far.
In plain English
This is a man-made peptide (a small protein fragment) that has a salicylic acid-like part attached. In skincare, it's meant to tell your skin cells to make more collagen and elastin, which can help your skin feel firmer and look smoother over time. Because it's a peptide, it's generally gentle and unlikely to clog pores or cause irritation for most people.
Quick decision guide
Useful, but context matters
Acetylsalicyloyl Pentapeptide-33 is generally a lower-concern ingredient when the full formula suits your skin.
Plain-English read
Treat this as a practical screening step before you compare products that contain this ingredient.
- Step 1Start with the score, then check the irritation and clogging risk before judging Acetylsalicyloyl Pentapeptide-33.
- Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
- Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.
Score terms in plain English
Irritation risk
lowLess likely to sting, burn, or bother most users, though sensitive skin can still react.
Clogging risk
lowLess likely to feel heavy or contribute to clogged pores for most skin types.
Evidence level
emergingThe ingredient may be promising, but claims should be treated more cautiously.
What it is
Acetylsalicyloyl Pentapeptide-33 is a synthetic peptide engineered by attaching a salicylic acid derivative (acetylsalicyloyl) to a chain of five amino acids (pentapeptide-33). It is designed to be stable in formulas and to target skin firmness.
How it works
Once applied, the peptide portion is thought to bind to receptors on skin cells and signal them to produce more collagen and other structural proteins. The salicyloyl group may help the peptide penetrate the outer layer of skin and also provide mild exfoliation or soothing properties, though the main action is the peptide signal.
Pros
Gentle collagen support
This peptide is designed to encourage collagen production without the irritation that some active ingredients (like retinol) can cause, making it suitable for sensitive skin.
Stable in formulas
Because it's synthetic, it stays effective in skincare products longer than some natural peptides, so you get consistent benefits from your bottle.
Cons and cautions
Limited human research
Most evidence comes from lab or animal studies; there aren't many large human trials proving this exact peptide works as claimed.
Slow results
Like most peptides, you'll need to use it for several weeks to months before seeing any visible change in firmness or lines.
Best for
- Anyone looking for a gentle anti-aging ingredient
- People with normal, dry, or combination skin who want to support collagen
Use caution if
- Those with known salicylate allergy (rare, but possible)
- Anyone seeking immediate or dramatic wrinkle reduction
Usage tips
Safety summary
Acetylsalicyloyl Pentapeptide-33 is considered safe for topical use in cosmetics at typical concentrations. Allergic reactions are very rare, but anyone with a known salicylate allergy should patch test first.
Research notes
Research on this specific peptide is still emerging. Early lab studies suggest it can stimulate collagen synthesis, but independent human clinical trials are scarce. Most evidence is extrapolated from similar peptide technologies.
Common label clues
- Typical concentration
- 0.1% to 1%
- Regulatory status
- Approved as a cosmetic ingredient in the EU, US, and other major markets. It is not a drug and cannot claim to treat or cure skin conditions.
- Common uses
- Anti-aging serums, Firming creams, Eye treatments
- Environmental note
- As a synthetic peptide, it is produced in a lab, which reduces the need for plant or animal harvesting. Its environmental impact is considered low compared to some natural extracts.
Good to know
- This peptide is often found in anti-aging serums alongside other peptides or antioxidants.
- The 'salicyloyl' part is not the same as salicylic acid; it's a modified version that is much less likely to cause dryness or peeling.
Common questions
What is Acetylsalicyloyl Pentapeptide-33 in beauty products?
This is a man-made peptide (a small protein fragment) that has a salicylic acid-like part attached. In skincare, it's meant to tell your skin cells to make more collagen and elastin, which can help your skin feel firmer and look smoother over time. Because it's a peptide, it's generally gentle and unlikely to clog pores or cause irritation for most people.
What does Acetylsalicyloyl Pentapeptide-33 do in a beauty product?
Once applied, the peptide portion is thought to bind to receptors on skin cells and signal them to produce more collagen and other structural proteins. The salicyloyl group may help the peptide penetrate the outer layer of skin and also provide mild exfoliation or soothing properties, though the main action is the peptide signal.
Is Acetylsalicyloyl Pentapeptide-33 safe for most people?
Acetylsalicyloyl Pentapeptide-33 is considered safe for topical use in cosmetics at typical concentrations. Allergic reactions are very rare, but anyone with a known salicylate allergy should patch test first.
Who should be careful with Acetylsalicyloyl Pentapeptide-33?
Those with known salicylate allergy (rare, but possible) Anyone seeking immediate or dramatic wrinkle reduction
Research sources
Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.