Sensitive Skin Care, Uncategorized

Maladies, Melodies, Allergies: The MCI/MI Allergy Saga Continues

Three years ago I wrote a post about an allergic reaction I developed around my eyes and the saga of being diagnosed with an allergy to a preservative called Methylisothiazolinone/methylchloroisothiazolinone (or MI/MCI for short). You can read the full post here, but it basically boils down to the idea that I am allergic to a chemical preservative that’s found in all kinds of water-based products, including:

  • Shampoo/Conditioner
  • Cosmetics
  • Liquid soaps
  • Dish detergent/washing up liquid
  • Laundry detergent and softener
  • Adhesives
  • Paint
  • Sunscreen
  • Baby wipes/makeup wipes

Even three years later, the post receives a lot of Internet traffic, which is a bit of a double-edged sword. I’m obviously pretty excited that people are still finding my blog, but I’m also devastated that it’s this stupid allergy that’s bringing people here. (And if that’s why you’re here – I’m so sorry that you’re struggling!) In my first post, I’ve included some info for how to recognize and deal with an initial diagnosis. At this point, I have managed my allergy for three years and my skin has (mostly) gone back to normal (with the exception of an occasional flare-up when my confidence gets too big for its britches and I try a new perfume sample like an absolute dodo), so please know that there is hope!! There are three years, a few more pounds, and a whole bunch of product trial and error between these two photos (but my dark circles are here to stay. Just part of my face’s charm):

Music Store Etsy Banner

This is a follow-up post to share some some things I’ve learned over the past three years,  but before we get into that, here are some disclaimers: First,  I urge you to get patch-tested if you can afford it. There are all kinds of crazy allergies out there, and instead of helping yourself, you could be making your allergy more severe by self-diagnosing and unknowingly continuing to use products that contain the actual culprit of your allergic reaction. (Trust me – I’ve been there!) Second, I am not a dermatologist or a medical doctor, and the severity of my allergy may not be the same as yours. So you should really check with a dermatologist first instead of taking my advice to heart. I’m simply sharing my experiences of what has worked for me, so here are some things I wish I’d known.


When I first got my patch test results, I had to hunt all over the Internet for information (and, if I had to guess, you’re reading this blog right now because that’s what you’re doing too). There are loads of helpful Facebook groups if you search for them. I practically lived on these forums when I was first trying to get my allergic reaction under control, and there are lots of helpful people going through the same issues. But there are two things to be aware of here.

First, as with the rest of the Internet, there are lots of people who put themselves forward as experts when in fact they are simply expressing an opinion. For example, after spending time in these Facebook groups, I thought I’d never be able to use anything scented ever again, which was devastating to me because I adore perfume and smelly-good things. But that’s because so many people dealing with this allergy have gone cold-turkey from fragrance, and that’s their prerogative.  I’ve used lots of fragranced products since being diagnosed and I’ve been fine, but that’s not to say that your experience will be the same as mine. Our allergies are all different, our skin is all different, and it’s very much an issue of trial and error.

Second, members of some of these Facebook groups are not always vetted,  and it can become a breeding ground for mid-level marketers selling “organic” or “natural” cosmetics or skin care. They pretend to suffer with the same allergy and then sneakily suggest miracle products that have worked for them. Then – lo and behold – they just so happen to sell this product too. Because I was desperate for something I could use as makeup or shampoo or moisturizer when I was first diagnosed, I wasted so much money trying out random things sold to me by people I thought understood my allergy because they had it too. (It turned out several times that not only did they not suffer with the allergy, but the product they sold me actually did contain MI/MCI!) I think many Facebook group admins are getting much better about keeping this type of member out of their groups, but it’s still something to be aware of! (But, on the whole, there are many lovely, helpful members in these groups, and I’d still be struggling without them, so please don’t let that put you off – just be aware!)


It has taken a lot of trial and error with products for me to regain some sense of normalcy. Mostly error. The transitional period can be uncomfortable, itchy, and painful, but it can be less uncomfortable, itchy and painful if you learn from my mistakes! Because I was so caught up in trying to replace my makeup and soap and shampoo, it didn’t even occur to me that the following things might be an issue…until they were an issue.

  • MaxiPads/Sanitary Products: I have no idea why corporations think women’s periods need to smell like baby powder or flowers, but I’ve unfortunately learned the hard way that many of these products contain fragrance. They’re particularly sneaky because the packaging is hardly ever labeled as fragranced or scented, but you can usually tell by smelling it. I know that sounds super awkward, but if you think that standing in the aisle of a store sniffing packages of maxipads is uncomfortable, then you definitely don’t want to experience the allergy flare-up that can appear after using one of these.
  • Toilet Paper/Loo Roll: Same as above. You’ll want to make sure you buy unscented, and you don’t want them to contain lotion.
  • Bandaids/Plasters: The adhesive in many brands can contain MI/MCI, though they never seem to be clearly labelled.
  • Scented Candles: So many of these contain MCI/MI, and there’s nothing worse than adding a chemical you’re allergic to into the air that you’re breathing. (Except for maybe using a scented maxipad or fragranced toilet paper. Just… trust me.)


I’ve found the the best way to determine if a product is safe to use is simply to ask. Many companies are happy to tell you whether or not their products contain MCI/MI (although many others won’t respond to you at all.) The difficult part is knowing exactly how to ask, because as I discussed in my first post, MCI/MI may not be listed in the ingredients of a product, but the fragrance mix may still contain it. So getting a list of ingredients may not tell you the whole story. To make things even more complicated, the majority of the people replying to your email are not dermatologists or chemists – they’re nice people paid to respond to customer queries, so it’s very unfair to assume they’ll know exactly how to answer your question. The easiest way to get the information you need is simply to explain it. To make things easier, I’ve provided a template for you here that you can simply copy and paste into the body of an email to a manufacturer:

I am allergic to the chemical preservatives Methylisothiazolinone/methylchloroisothiazolinone (commonly known as MI and MCI) as well as other -isothiazolinones. I have two questions I hope you can answer for me.

First, could you please confirm if EXAMPLE PRODUCT contains any of the above ingredients.

Second, because added fragrance or perfume can sometimes include MI, MCI, or  other -isothiazolinones without actually being listed in the ingredients, could you please confirm if EXAMPLE PRODUCT contains any of the chemicals listed above in its fragrance mixes?

This is a great way to get the information you need (but always remember that manufacturers can change their ingredients at any point, so it’s always good to keep checking!) I’ve found MI/MCI  safe products through direct correspondence with many companies.(As an example, Lush is always quick and thorough with a response, and as a result, that’s where I buy most of my cosmetics and bath products.)

I hope that some of that is helpful! If you have any questions about the MI/MCI allergy or want to swap tips or product recommendations, I would love to hear from you! Feel free to comment below or to drop me an email.

3 thoughts on “Maladies, Melodies, Allergies: The MCI/MI Allergy Saga Continues”

  1. Thank you for this update!
    Your blog helped me so much. I have to wait 6 weeks before I can see an allergist so I still do not know what I am allergic to but after I eliminated the MI products from my home, I was able to at least go out into public and work without wearing sunglasses. I see the allergist this week – – finally – – and thanks to your blog I have been taking pics of my eyes each day. I will be able to show her the good, the bad and the really ugly.
    Thank you again for sharing your experiences.


    1. Hi Julia! Thank you so much for your kind words and for letting me know about your experiences!! I hate that you’re having to deal with an allergic reaction, but I’m thrilled that you finally get to see the allergist after waiting so long. I really hope that you’re able to get it all under control and get your life back to normal – I totally feel for you!! ❤ If it does end up being MI, feel free to get in touch if you need any help with anything!


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