What Causes Clitoral And Vaginal Itching?

Hello, my clit has been itching as well as a little inside the vaginia, but most itching takes place on the outside, and I notice that when i put cream on to stop the itching, it goes away but after i urinate the itching comes back? Just wanting any ideas, I have been doing monistat treatment, with some relief but doesnt seem to be going away....