One of my friends had a mild case of rashes (sounds like yours) but she didn't managed to identify the cause. It went away after a few weeks. Her doctor thought it may be an allergic reaction to something but she never found out the reason behind it.
During those few weeks, she applied moisturizer and the medication (and she only took the prescribed antihistamine when the itch was unbearable) given by the doctor to help ease the itch.
Sorry, can't be more helpful other than sharing what my friend did.
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