Why Am I Getting an Armpit Rash?

Clean beauty industry maven Mary Futher founded kaia naturals® after spending 20 years working for global beauty companies. Mary now shares her weekly content series, delivering a quick fix, home remedy, or clean beauty product suggestion for a variety of human discomforts that some may find too embarrassing to discuss.

Do You Suffer From Armpit Rashes?

When using natural deodorant, ⅔ of us have probably experienced an armpit rash of some sort. It’s actually very common and happens more than expected. As someone who does not have sensitive skin normally, I was shocked that I had developed a flaming red, itchy rash when I was testing a new natural deodorant a few years ago. I’ll never forget that time because I was on vacation and that armpit rash was so painful, it practically ruined the entire trip! I automatically blamed the ingredients in the deodorant for the rash, but knowing what I know now, it could have been caused by something else. Most of us will automatically jump to the conclusion that deodorant ingredients is to blame. While that may be true sometimes, it’s important to recognize other common causes to properly diagnose.


But first, let’s clarify that not all natural deodorants are the same. Ever heard the saying “Calories are not created equal”? Well, it’s the same for natural deodorants. As I talked about in a previous post a few weeks ago, some natural deodorants are formulated with irritating and harsh ingredients. As the skin on our armpits are one of the most sensitive areas, it’s very important that gentle yet effective ingredients are used there.

TIP: If you have sensitive skin, it’s best to avoid deodorants that contain baking soda (sodium bicarbonate) or essential oils listed in the first or second line of the ingredient list. This means the ingredients are used at very high levels and could cause irritation and rashes.

baking soda can cause armpit rashes

Natural deodorant almost got me divorced!

Many years ago when natural deodorants were just starting to appear on the market, I wanted my husband to switch from antiperspirant to natural deodorant with me. He was totally on board and the first 3 days were fine for the both of us. Then one morning I could hear my husband yelling in pain (his pain tolerance is quite high I might say). He lifted both his arms to reveal two flaming red rashes under each arm. It was so painful he couldn’t barely move his arms. When I had looked at the ingredients, that’s when I saw that the first ingredient was baking soda, a known skin irritant. Needless to say, I had a very annoyed and angry husband afterwards. Oops, hehe! This is also the main reason why I would never use baking soda in my own natural deodorants, as many people have the same reactions as my husband.


Moisture rash or Intertrigo, is when a rash forms in skin folds, such as armpits and the skin under breasts. The skin folds traps moisture and the skin-to-skin friction irritates the skin, kind of like when babies get a diaper rash. This type of armpit rash is very common because when using natural deodorant, your underarms are more likely to sweat as there is no aluminum chloride plugging your sweat ducts.

TIP: Keep skin dry by applying a natural powder like cornstarch or arrowroot powder overtop armpits to help absorb excess moisture.


razor - armpit rashes - kaia naturals

We all know that shaving is annoying and sometimes painful, especially when you’re in a rush. Well, good news, I’m here to tell you another reason to drop the blade: It’s also irritating to your skin. Especially when you shave against the grain, the blade of the razor tugs at the hair, pulling it away from the skin causing more irritation. Not shaving properly can lead to razor burns and bumps, causing red rashy irritated armpits.

TIP: Shave hair in the direction your hair grows, not against it. Always use a buffer like shaving cream so that it acts like a thin barrier. Never apply deodorant right after shaving, as this can also cause further irritation. Shave at night and let skin heal overnight before applying deodorant.


clothes that give me an armpit rash

Who would have thought… yes, your clothing can also be a cause for an armpit rash. If a top is too tight to your underarms, the sleeves could be blocking your pores, which prevents your sweat from evaporating. Moisture gets trapped under your skin and causes a heat rash. Luckily, heat rashes aren’t serious and they typically go away within a few days. The best way to prevent them is to stay in cool environments and of course, wear loose-fitting clothing. Once again, during the detox transitional phase, you may be sweating more, so it’s important to be wary of this.


Everyone has Candida—a type of fungus—on their skin, but too much of it can cause rashes called candidiasis. A lot of factors can cause Candida overgrowth: tight clothing, poor hygiene, pregnancy, taking antibiotics, a poor immune system, and even living in a hot, humid climate can cause an infection. These rashes also tend to develop in damp parts of your body. As your armpits could be damper than usual during the 30-day transitional phase and when using natural deodorant, that means they’re especially at risk! Apart from candidiasis, other infections can cause armpit rashes. According to this academic article, for moisture-associated skin damage (MASD) to occur, moisture and bacteria must also be present on the affected area. As we all know, our armpits are a breeding ground for bacteria, especially during the stages of detox. Bacteria plus wetness is a recipe for a body odor…and a rash! To find out if you may have candidiasis, consult with your doctor.


Just like Candida overgrowth, eczema rashes can be caused by different factors such as dry skin, stress, our harsh Canadian winters, and all sorts of irritants like metals, fragrances and household products. Even completely natural irritants like juices from fruits and vegetables can cause a reaction. Researchers believe it’s a mix of an overreactive immune system, gene mutations and triggers in the person’s environment that can cause eczema. To find out if you may have an eczema rash, consult with your doctor. To learn more about how to switch to natural deodorant successfully, read why some of them don’t work.

Let us know if you’ve had an experience with natural deodorants or armpit rashes that you’d like to share.


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