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Another cosmetic ingredient to be afraid of

Lindsay’s looking for information:

What is quaternium/polyquaternium? If you have allergic contact dermatitis to quaternium-15 should you avoid contact with any other poly/quaternium numbers?

The Left Brain helps her out:

Quaternium and Polyquaternium (or “Quats” for short) are the names of CATEGORIES of chemicals. There are many different chemicals in each category. For example, there’s Quaternium 15, 18, 24, 27, 80 and Polyquaternium-6, 7, 10, 11, and 28 to name a few.

Quat doesn’t mean squat

Unfortunately, the name doesn’t really tell you anything about the chemical itself. The actual chemical name of Quaternium 15 is Methenamine 3-chloroallylochloride but it’s also known as 3,5,7-Triaza-1-azoniatricyclo(,7)decane, 1-(3-chloro-2-propenyl)-, chloride; N-(3-Chloroallyl)hexaminium chloride; and Hexamethylenetetramine chloroallyl chloride. You can see why we call it “Quaternium-15” for short!

Anyway, this particular quat is a preservative – it keeps bugs from growing in your cosmetics. It works by releasing formaldehyde, which probably explains your reaction to it. Other quats may have similar names, but that doesn’t mean they will react with your skin the same way. For example, Quaternium-18 is a long chain fatty conditioning agent and Quaternium-80 is a silicone based conditioner. The chemistry of these Quats is completely different from number 15.

The Beauty Brains bottom line

Not all Quats are created equal. Stay away from Quat-15 if you know it gives you problems but that doesn’t mean you have to shy away from the rest. I assume you’re not the only person with this question and it will be interesting to see if any companies begin offering “Quat-free” products. But so far, the “naturals” crowd don’t seem too worried about Quats. Jason Natural Cosmetics, for example, are pretty picky about their ingredients and they have an Apple and Green Tea shampoo that contains polyquats.

By the way, if you’re not sure if you have contact dermatitis or not, read our previous post on how to tell the difference between skin allergies and skin irritation.

{ 11 comments… add one }

  • Beth Bee January 19, 2015, 9:08 pm

    Thank you for this! I was recently diagnosed with an allergy to Quaternium-15 that’s pretty severe. When I was looking at some conditioners, I kept seeing Quaternium-80 and didn’t know if it would be safe! My allergist was qclosed all weekend, so I thought I’d give google a try before calling he next week, and I stumbled upon your site. I still plan on calling my allergist to confirm, but you saved me a lot of anxiety!

  • Cecilia May 29, 2015, 11:15 pm

    My 13 year old daughter has been using j&j baby shampoo since she was a baby. It has polyquaternium 10, it this ingredient bad? Thanks.

  • BOBBI June 10, 2015, 4:27 pm



    • Randy Schueller June 10, 2015, 5:08 pm

      Look for non-conditioning shampoos. I think Suave has some products without PQ. How do you know that’s the ingredient that makes you itch?

  • Jodi Williams July 31, 2015, 2:04 pm

    I’ve recently been diagnosed with an allergy to Quaternium-15. I’m a little overwhelmed at how to go about checking ingredients in everything I put on my body. Do you know of a reliable database that could help? Some of what I use comes from Target, etc., but a lot of what I use comes from online sources, beauty stores, etc. I’m not having great luck searching for specific brands and their ingredients, which I find strange. I’d greatly appreciate any help you can offer!

    • Randy Schueller July 31, 2015, 4:11 pm

      Hi Jodi. I’m sorry to hear about your allergy. There’s no single data base that will tell you every product that uses a specific ingredient like Quaternium-15. You’ll have to look at each one on a case by case basis. For any product that you buy at Target you can just look at the label and look for it. Online is a little tougher because not all companies list ingredients on their websites. I found that websites like drugstore.com and Walgreens.com are very good for looking up ingredients for products. Good luck!

  • Michelle September 4, 2015, 9:15 am

    I have recently had a skin test confirming that I am allergic to Quaternium-15. My contact lens solution contains polyquaternium-1. Should I stay away from that contact lens solution?

    • Randy Schueller September 4, 2015, 3:51 pm

      Polyquaternium-1 is not the same thing as Quaternium-15. (Of course it’s always possible that you’re allergic to both…)

      • Michelle September 5, 2015, 4:43 pm

        Thank you!

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