Thank you for the question.
Determining the cause of your itchy rash is of course important for the correct treatment to be prescribed. It is not entirely clear from the photo what the cause of your rash is.
However, taking some antihistamines usually helps control the itch in 20-30 minutes. Making sure your skin is well moisturised with emollients, or ones containing menthol can also improve the skin barrier and soothe the skin.
Hope this helps!
