Aluminum Sesquichlorohydrex Pg: What Is It, Cosmetic Uses, Benefits & Side Effects

Curious about this ingredient? In this article we're explaining exactly what it is and why it's used within cosmetic formulations.
Updated on: June 23, 2025
Share:
Inside this article:

All information on this page is verified using publicly available nomenclature standards and reference materials from The Personal Care Products Council (PCPC) and the European Commission's CosIng database. Our analyses are based on technical data from these sources to ensure accuracy and reliability.

What Is Aluminum Sesquichlorohydrex Pg?

Aluminum Sesquichlorohydrex Pg is a compound created when aluminum chloride hydroxide reacts with propylene glycol, a common solvent made from corn sugar or petroleum. The result is a stable aluminum salt that dissolves well in water based formulas. It belongs to the same family as the aluminum salts that have been used in underarm products since the 1940s.

The move from older aluminum chlorides to Aluminum Sesquichlorohydrex Pg happened because chemists wanted an ingredient that worked just as well but was kinder to skin and had a smoother feel. By linking the aluminum complex to propylene glycol they achieved better spreadability, lower sting and less chance of white marks on clothing.

Manufacturers first produce high purity aluminum hydroxide then treat it with hydrochloric acid while controlling pH and temperature. Propylene glycol is added during or after the reaction to bind with the aluminum complex. The finished solution is filtered, concentrated and tested for exact aluminum content before it is shipped to cosmetic labs.

You will mostly find Aluminum Sesquichlorohydrex Pg in roll-on and stick deodorants, aerosol antiperspirant sprays, underarm creams, body powders and foot sprays. It can also appear in certain intimate area freshening products that aim to reduce moisture and odor.

Aluminum Sesquichlorohydrex Pg’s Cosmetic Benefits/Uses

This ingredient brings several helpful actions to personal care formulas

  • Antiperspirant: Forms temporary plugs inside sweat ducts which slow down the flow of sweat. This keeps underarms and other areas drier for many hours and helps clothing stay fresh.
  • Astringent: Causes a mild tightening effect on skin proteins that can make pores look smaller and reduce surface moisture. This supports the antiperspirant action and gives a clean dry feel.
  • Deodorant: Limits the growth of odor causing bacteria thanks to its aluminum ions that create an environment where these microbes struggle to thrive. Less bacteria means less body odor even if some sweat still reaches the surface.

Who Can Use Aluminum Sesquichlorohydrex Pg

Most people with normal, oily or combination skin can use products that contain Aluminum Sesquichlorohydrex Pg without trouble. Those with very sensitive or eczema-prone skin may notice stinging or redness, especially if the product is applied right after shaving or on broken skin, so extra caution is advised.

The ingredient is synthesized from aluminum salts and propylene glycol, neither of which comes from animals. Because no animal-derived substances are involved it is considered suitable for vegans and vegetarians, though final product testing policies vary by brand.

Regulatory agencies regard topical aluminum salts as safe for use during pregnancy and breastfeeding because only tiny amounts penetrate the skin. Even so, this is not medical advice; anyone who is pregnant or nursing should check with a healthcare professional before adding a new deodorant or antiperspirant to their routine.

Aluminum Sesquichlorohydrex Pg does not make skin more sensitive to sunlight, so it will not increase the risk of sunburn. It is also free of fragrance and dyes in its raw form, which can be helpful for people trying to avoid those additives.

Potential Side Effects/Adverse Reactions

Reactions to topical Aluminum Sesquichlorohydrex Pg differ from person to person. The following points describe potential side effects that could occur, but they are uncommon when the ingredient is used at the levels found in finished cosmetics.

  • Skin irritation such as redness, burning or itching
  • Dryness or tight feeling in the underarm area
  • Mild swelling or bumps caused by clogged sweat ducts
  • Contact dermatitis in individuals allergic to aluminum salts or propylene glycol
  • Increased stinging if applied to freshly shaved or broken skin

If any of these effects occur stop using the product and seek advice from a qualified healthcare provider.

Comedogenic Rating

Rating: 1 / 5

Aluminum Sesquichlorohydrex Pg is water soluble and does not leave an oily or waxy residue that could trap sebum in facial pores. While its antiperspirant action can temporarily block sweat ducts in the underarm area, it is not known to obstruct sebaceous glands that lead to acne. The propylene glycol portion is likewise considered very low on the comedogenic scale, so the overall likelihood of pore clogging is minimal.

Suitable for acne-prone or breakout-prone skin, especially since it is usually used on underarms rather than the face.

People with very reactive skin may still experience follicular irritation bumps, but these are heat or sweat related rather than classic comedones.

Summary

Aluminum Sesquichlorohydrex Pg acts as an antiperspirant, astringent and deodorant. It works by forming tiny gel plugs that slow sweat flow, tightening skin proteins to reduce surface moisture and creating an environment that discourages odor causing bacteria. All of this happens while staying water soluble enough to rinse away with regular washing.

The ingredient is a staple in modern stick, roll-on and spray antiperspirants but is rarely found in facial products. Its long history of effective wetness and odor control keeps it popular with mainstream brands though some natural-leaning lines choose to avoid aluminum salts altogether.

Safety assessments by regulatory bodies rate topical use as low risk, with most users experiencing no issues beyond occasional mild irritation. As with any new personal care product it is wise to patch test to ensure your individual skin tolerates the formula.

Was this article helpful?
More from Glooshi:
ADVERTISEMENT
Get all our top headlines in beauty.
Delivered right to your inbox each week. Zero spam, all goodness, opt-out at anytime.
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Get the latest beauty news, top product recommendations & brand-exclusive discount codes direct to your inbox.
Send good feedback:

All feedback is greatly appreciated, anonymous, and will be used to improve the quality of our articles.

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Send bad feedback:

All feedback is greatly appreciated, anonymous, and will be used to improve the quality of our articles.

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Search