I am experiencing a mild tingling sensation in my armpit, what could it be?
It is not painful, but the skin is sensitive on the underside of my tricep, and I have a 2 inch rash on the upper part of my back near the same armpit.
It sounds as though this is quite a change from your usual state of health. In this kind of situation, the best thing to do is make an appointment to see your primary care physician right away. He or she will know your health history and medications and can also examine you to help determine if this is nothing to worry about or whether a more thorough and detailed investigation might be necessary. From the symptoms you report, it is possible that this is nothing serious--perhaps a reaction to a new deodorant or detergent. However, it is also possible that this could represent the very early prodrome of a zoster infection (otherwise known as shingles) which can cause significant pain and be a threat to those--including yourself--who might have a weakened immune system. Distinguishing between the possibilities, and particularly making the determination about how critical your symptoms are--requires knowing more about you (for example, you are much more likely to develop shingles as you age), your health history (these symptoms would be more worrisome in an immuncompromised patient who had just completed chemotherapy, for example), and being able to examine your arm. If you don't have a primary care physician, this is a good time to find one!
This answer is for general informational purposes only and is not a substitute for professional medical advice.
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