Suggest Treatment For Rash On The Skin

I have a rash on my the right side of my face below my chin. Its starts out as a red spot that itches within an hour it becomes water like blisters. The blisters will leak and become crusted within days and it goes away. I have had this happen to me since childhood, appearing only on the right side of my face on my chin or below my chin. I have never really known the cause, but have thought it to be an allergic reaction to citric acid. Can you please tell me what it is?

I have a rash on my the right side of my face below my chin. Its starts out as a red spot that itches within an hour it becomes water like blisters. The blisters will leak and become crusted within days and it goes away. I have had this happen to me since childhood, appearing only on the right side of my face on my chin or below my chin. I have never really known the cause, but have thought it to be an allergic reaction to citric acid. Can you please tell me what it is?