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"Why do I have a rash on the outside of my upper arms after I shower?"

ZocdocAnswersWhy do I have a rash on the outside of my upper arms after I shower?


I'm a 25 year old single women and work primarily in doors. About 7 years ago I moved and I though I was having an allergic reaction to the water in my new home because everytime I shower I get a red dry rash on my arms. This still happens today, can it be a heat rash? I do not take any medications for this and have not seen a doctor.


The symptoms you are describing sound like the condition known as keratosis pilaris, also known as KP. It is very common and causes rough patches or acne-like bumps that are most often seen on the outside of arms, front of thighs, and sometime on the buttocks. The affected skin does not usually itch or hurt. The skin can feel like sandpaper to the touch. Keratosis pilaris runs in families and results from the buildup of keratin, which is a protein that protects your skin. You may notice that it seems to improve somewhat during the summer. The good news is that keratosis pilaris gradually resolves on its own in most cases. The bad news is that treating it before it goes away on its own can be frustrating. The reason that you may have first noticed the rash when you moved is possibly due to a change in the water. Keratosis pilaris is aggravated by dry conditions so if you have soft water where you lived before and now have hard water this can dry out your skin and exacerbate your symptoms. Try to take lukewarm showers, use a gentle soap, pat dry and use a good quality moisturizer. It is important to see your primary care provider or dermatologist to determine the exact nature of your rash and discuss appropriate treatment.

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