Hi,
Welcome and thanks for posting your query to Healthcare Magic.
After reading your query it appears the possibility of "Urticaria". It is a common condition caused by bursting of
allergy producing cells known as "mast cells". As the chemical inside them is released it produces a rash which you have mentioned. There can be multiple factors producing this condition which are included in day to day life and some times it is really difficult to find one exact cause. In your case stress just before menses can cause the bursting of the cells.
For the betterment kindly follow the suggestions below:
-Apply over the counter
calamine lotion 3-4 times a day.
-You can do cold water compresses to reduce the intensity of itching.
-Do not scratch or rub the skin as it can lead to further aggravation.
-The best measure is to take oral anti
histamine like
loratadine or levocetrizine under medial advise.
G6PD enzyme deficiency generally do not cause any rash per say so do not worry about the same.
In between next time if the rash appears before menses then you can
consult a dermatologist who can diagnose it exactly.
Hope these information will help.
"With good health wishes"
Dr Sanjay Kumar Kanodia
MD (Dermatology & STDs)