Hi,
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Avoid shaving so very often as you would affect the normal secretions and cause dryness which in turn would precipitate itching within sometime. Change your razor often. Visit your doctor/gynecologist for examination to rule out any infective causes. Drink plenty of water. You can also consider applying Caladryl lotion or Aloe vera lotion for temporary relief to soothe the itching (these will not cure the infection, but only provide temporary relief).
Take care.