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Member Since 22 Apr 2013
Offline Last Active Apr 29 2013 03:54 PM

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Why Do These Products Clash? Any Scientific Minds Know About Ingredients? (Zinc Oxide N...

22 April 2013 - 10:05 PM

Hello all,


I was a member many years ago. Am having a raging return of various skin problems, which I'll cover another time in another topic - or this will get way too long.


For now, I'm just trying to understand why two (or three) products that I use do not seem to get along well.


What did work:

Since about 2004 I had been using cetaphil cream with Alpha Hydrox's oil free 10% AHA. No problems during all this time. They play very well together.


Where things started going wrong:

Only about a month ago, I began experimenting with adding plain zinc oxide powder to my cetaphil cream. It was pretty magical for me to see  how it improved breakouts on my back, shoulder, and chest overnight. (I have other stuff for my face presently - long story.)


Here's the thing - I can apply the cetaphil cream / zinc oxide mix to my skin with no problems. There is no weird smell. It might smell barely medicinal, but I like that smell, it's clean smelling. It smells normal. It works nicely too.


However, anytime I put on my old AHA over top of where the zinc mixture had been the night before - or even when I put the AHA on after I've washed off the zinc mixture off (I know the zinc stays on my skin even after washing somewhat) - I can smell something like ammonia where the AHA seems to mix with what's left of the zinc oxide. The smell reminds me of when I was young and I would get my hair permed - that sort of ammonia smell - at least I think that's what it is.


This seems so strange.

  • Cetaphil cream is made to go well with everything - that's its purpose: to work well with various acne medications and be benign.
  • Zinc Oxide is used for the most bland and safe sunscreens that even babies are permitted to use.
  • The AHA says you're supposed to wear a sunscreen - so it seems to me it should work okay with a product containing zinc oxide.


HOWEVER, when I contacted the manufacturer of the AHA and asked them why the ingredients were clashing, they informed me that their chemists did NOT have a clue why, nor did they ever test their AHA with zinc oxide to see how it would react. They just said it sounds like a chemical reaction. Not comforting.


So I'm coming here - hoping someone with a scientific mind might know what's going on. It doesn't hurt my skin that I can see, but that smell can't be right. I am so eager to use it again - because it works so well on my breakouts - but I can't stand the idea that I'm poisoning myself with that ammonia like odor that gets produced.


What is it?


Here are the ingredient lists of the products:


Zinc Oxide - just pure zinc oxide powder - the white stuff - in a large micron size.



Water, Glycolic Acid, Ammonium Hydroxide, Sodium Lactate, Green Tea Extract, Carrageenan (Red Seaweed) (Sea Kelp Extract), Panthenol (Vitamin B5), Propylene Glycol, Diazolidinyl Urea, Methylparaben, Propylparaben, PVM/MA Decadene Crosspolymer



Cetaphil Cream:

Water, Petrolatum, Glyceryl Polyglycerylmethacrylate, Dicaprylyl Ether, Glycerin, Dimethicone, Glyceryl Stearate, Cetyl Alcohol, Prunus Amygdalus Dulcis (Sweet Almond Oil), PEG 30 Glyceryl Stearate, Tocopheryl Acetate (Vitamin E), Benzyl Alcohol, Phenoxyethanol, Sodium Hydroxide, Acrylates/C10 30 Alkyl Acrylate Crosspolymer, Dimethiconol, Disodium EDTA, Propylene Glycol





PS: I have ordered a body wash and shampoo with 14% glycolic acid called Aqua Glycolic - and am hoping and praying it might play better with the zinc. Am also hoping to order a plain zinc sunblock with fewer ingredients than the cetaphil cream in hopes that might help. Am getting desperate. I am 10 days from going somewhere very important.