Ingredient review

Aluminum Sesquichlorohydrex PEG

INCI: Aluminum Sesquichlorohydrex PEG

Aluminum Sesquichlorohydrex PEG is a common antiperspirant active that effectively reduces sweat but may cause irritation for sensitive skin.

beautypersonal careantiperspirant

In plain English

This is a type of aluminum salt used in antiperspirants. When applied to your underarms, it dissolves into a gel-like substance that temporarily plugs your sweat glands, stopping sweat from reaching the surface. The 'PEG' part helps the ingredient dissolve better and feel less sticky on skin. It's not a deodorant (which masks odor) — it physically blocks sweat.

Quick decision guide

Useful, but context matters

Aluminum Sesquichlorohydrex PEG can be useful, but watch for some irritation potential.

Plain-English read

Treat this as a practical screening step before you compare products that contain this ingredient.

  1. Step 1Start with the score, then check the irritation and clogging risk before judging Aluminum Sesquichlorohydrex PEG.
  2. Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
  3. 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

moderate

Can bother some users, especially with frequent use, damaged skin, or strong companion ingredients.

Clogging risk

low

Less likely to feel heavy or contribute to clogged pores for most skin types.

Evidence level

strong

There is a stronger practical or research basis for the ingredient role described here.

What it is

A synthetic aluminum compound modified with polyethylene glycol (PEG) to improve solubility and reduce irritation compared to basic aluminum chlorohydrate.

How it works

When applied to the skin, the aluminum ions are absorbed into the sweat duct openings. There, they form a temporary gel plug that physically blocks sweat from being released. The plug naturally wears off over time as skin cells shed.

Pros

Highly effective sweat control

Clinically proven to reduce sweat production by forming temporary plugs in sweat ducts, providing all-day dryness for most users.

Improved formula feel

The PEG modification makes the ingredient more soluble and less likely to leave heavy white residue compared to older aluminum salts.

Cons and cautions

Can irritate sensitive skin

Especially if applied right after shaving or on broken skin, the aluminum compound may cause stinging, redness, or itching.

Not a deodorant

It only blocks sweat, not odor-causing bacteria. You may still need a separate deodorant or fragrance to manage smell.

Best for

  • People who experience heavy underarm sweating
  • Those looking for long-lasting wetness protection

Use caution if

  • Individuals with sensitive or easily irritated underarm skin
  • Anyone who prefers aluminum-free or natural deodorants

Usage tips

Apply to completely dry underarms — moisture can reduce effectiveness and increase irritation.
Use at night before bed for best results, as the product needs time to form plugs while sweat glands are less active.
Avoid applying immediately after shaving to minimize stinging.

Safety summary

Aluminum Sesquichlorohydrex PEG is considered safe for topical use in antiperspirants by major health agencies, including the FDA and SCCS. Some individuals may experience mild skin irritation, but serious side effects are rare. Concerns about aluminum absorption and long-term health effects have not been conclusively proven in scientific studies.

Research notes

Multiple studies confirm the efficacy of aluminum salts for sweat reduction. Research on aluminum absorption through skin shows minimal systemic uptake (less than 0.012% of applied dose). No strong evidence links cosmetic aluminum use to breast cancer or Alzheimer's disease, though some observational studies have raised hypotheses that remain unconfirmed.

Common label clues

Typical concentration
10–25% in over-the-counter antiperspirants
Regulatory status
Approved by the U.S. FDA as an over-the-counter antiperspirant active ingredient. The European Commission's Scientific Committee on Consumer Safety (SCCS) also considers aluminum compounds safe in cosmetics at current levels.
Common uses
Antiperspirants, Deodorants, Underarm creams
Environmental note
Aluminum mining has environmental impacts, but the amounts used in personal care are very small relative to industrial uses. PEG is biodegradable under certain conditions.

Good to know

  • Aluminum compounds are the only FDA-approved antiperspirant actives in the U.S.
  • The 'PEG' in the name refers to polyethylene glycol, a common solubilizer that helps the aluminum salt dissolve more evenly.

Common questions

What is Aluminum Sesquichlorohydrex PEG in beauty products?

This is a type of aluminum salt used in antiperspirants. When applied to your underarms, it dissolves into a gel-like substance that temporarily plugs your sweat glands, stopping sweat from reaching the surface. The 'PEG' part helps the ingredient dissolve better and feel less sticky on skin. It's not a deodorant (which masks odor) — it physically blocks sweat.

What does Aluminum Sesquichlorohydrex PEG do in a beauty product?

When applied to the skin, the aluminum ions are absorbed into the sweat duct openings. There, they form a temporary gel plug that physically blocks sweat from being released. The plug naturally wears off over time as skin cells shed.

Is Aluminum Sesquichlorohydrex PEG safe for most people?

Aluminum Sesquichlorohydrex PEG is considered safe for topical use in antiperspirants by major health agencies, including the FDA and SCCS. Some individuals may experience mild skin irritation, but serious side effects are rare. Concerns about aluminum absorption and long-term health effects have not been conclusively proven in scientific studies.

Who should be careful with Aluminum Sesquichlorohydrex PEG?

Individuals with sensitive or easily irritated underarm skin Anyone who prefers aluminum-free or natural deodorants

Research sources

FDA Antiperspirant Drug Products for Over-the-Counter Human UseOpenSCCS Opinion on Aluminum Compounds in CosmeticsOpenPubMed: Aluminum and Antiperspirants – Safety ReviewOpen

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.