Peg-3 Dioleoylamidoethylmonium Methosulfate: 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: July 1, 2025
Share:
Inside this article:

We verify all information on this page using publicly available nomenclature standards from The Personal Care Products Council (PCPC), the European Commission's CosIng database and documentation provided directly by ingredient manufacturers. Our analysis is based on technical data from these sources to ensure accuracy and reliability.

What Is Peg-3 Dioleoylamidoethylmonium Methosulfate?

Peg-3 Dioleoylamidoethylmonium Methosulfate is a synthetic conditioning agent created by linking fatty acids from olive or soybean oil with small units of ethylene oxide, then quaternizing the resulting molecule to give it a mild positive charge. Chemists first explored this class of ingredients in the late 1990s when formulators were looking for softer, more biodegradable alternatives to traditional quats used in hair care. Production involves reacting dioleoyl fatty acids with an amidoethyl group, adding an average of three ethylene oxide units, then neutralizing the mixture with methyl sulfate to create a water-dispersible salt.

Because the molecule carries a positive charge, it is especially good at bonding to the negatively charged surface of hair. You will most often spot it in rinse-off and leave-in conditioners, detangling sprays, masks, color-protecting treatments, lightweight creams, and some anti-frizz serums. Its gentle profile makes it popular in both salon and mass-market lines aimed at daily use.

Peg-3 Dioleoylamidoethylmonium Methosulfate’s Cosmetic Benefits/Uses

This ingredient earns its place in formulas by offering the following performance perks

  • Antistatic: The positive charge helps neutralize the static buildup that leads to flyaways and frizz so hair lies smoother and is easier to style
  • Hair conditioning: Forms a light, breathable film on the hair shaft that boosts softness, slip and shine while making wet hair less prone to breakage during comb-out

Who Can Use Peg-3 Dioleoylamidoethylmonium Methosulfate

Peg-3 Dioleoylamidoethylmonium Methosulfate is considered friendly for all skin and scalp types, including sensitive or dry scalps, because it is non irritating and does not clog pores. Those with very oily or acne-prone skin can also use it, as the molecule stays mostly on the hair shaft and rinses away cleanly from the skin.

The fatty acids used to make this ingredient typically come from plant sources such as olive or soybean oil, and no animal by-products are involved in its manufacture, so it is suitable for vegans and vegetarians.

Current research shows no specific risks linked to pregnancy or breastfeeding when the ingredient is used in rinse-off or leave-in hair products. This is not medical advice, and anyone who is pregnant or nursing should consult a healthcare professional before introducing new personal care products, just to be safe.

Peg-3 Dioleoylamidoethylmonium Methosulfate does not increase photosensitivity and there are no known interactions with common active ingredients like retinoids or alpha hydroxy acids.

Potential Side Effects/Adverse Reactions

Reactions to topical Peg-3 Dioleoylamidoethylmonium Methosulfate vary from person to person. The points below outline potential side effects only, and most users will not experience them when the ingredient is properly formulated in a cosmetic product.

  • Mild scalp redness or itching most often linked to overuse of a highly concentrated leave-in treatment
  • Eye irritation if the product accidentally drips into the eyes during application or rinsing
  • Contact dermatitis in rare cases for individuals who are sensitive to quaternary ammonium compounds
  • Build-up on very fine hair which can weigh strands down if the product is not rinsed thoroughly

If any discomfort or irritation occurs stop using the product and seek advice from a medical professional

Comedogenic Rating

Rating: 1 / 5

Peg-3 Dioleoylamidoethylmonium Methosulfate sits mostly on the hair shaft and is water dispersible so very little residue remains on facial skin or scalp after rinsing. Its fatty acid portion is balanced by a large hydrophilic head that keeps the molecule from packing into pores. For these reasons the chance of it blocking follicles is extremely low although not quite zero when used in heavy leave-ins or styling creams.

Suitable for acne-prone or breakout-prone skin in the vast majority of cases.

As with any conditioning agent build-up can occur if multiple products containing it are layered without proper cleansing which might indirectly aggravate congested areas.

Summary

Peg-3 Dioleoylamidoethylmonium Methosulfate conditions hair and tames static by delivering a mild positive charge that binds to the negatively charged cuticle. This ionic attraction forms a thin lubricating film that boosts slip softness and shine while helping strands lie flat and resist breakage.

It is not as famous as powerhouse quats like behentrimonium chloride yet formulators appreciate its lighter feel and plant-derived fatty acid base so you will find it sprinkled across newer gentle or eco-minded hair lines.

Current data shows it to be low risk for irritation or pore clogging when used at normal cosmetic levels. Still it is smart to patch test any new product to be sure it agrees with your individual skin and scalp.

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