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She should consider visiting her gynecologist at the earliest for thorough examination and further evaluation with hormonal analysis to rule out hormonal insufficiency as cause for vaginal dryness, a vaginal swab/smear test to look for any infective causes, local skin conditions, pinworm infection, chemical irritation etc. treatment as appropriate (based on examination findings and investigation results) would be started to help her control the symptoms. She should consider being in regular monitoring and follow-up with her treating gynecologist. Avoid use of harsh soap, perfumes etc in eth area. Drink plenty of water. Avoid vaginal douching. Avoid use of tight fitting clothes and avoid accumulation of sweat in the area. She should use loose cotton undergarments.
Take care.