Two years ago, I got really badly bitten by midges, and their bites always make time itch like mad, sometimes for months. Because of the sheer number of bites on that occasion, and the fact that a lot of them were blistering, I went to the pharmacy. Over a couple of weeks, I spent a fortune trying one 'remedy' after another, but none of them helped me in the slightest.
I hope you have more luck, travelsafar - it might depend what has bitten you and how your own skin reacts to it.