I do use since a long time the Noise Ninja plugin for Photoshop.
Photo Ninja is a newer product, made by the same developers of Noise Ninja, with added functionalities.
Although no longer supported by the developers, older versions of Noise Ninja are still made available in the Photo Ninja product website, just look for Noise Ninja legacy download links and look for one that you may install.
I had a quick look and they seem provided free of charge so try will not hurt the pocket ;-)
I have tested Photo Ninja (and also other noise reduction software along the way of learning astro image processing) but found that I liked more the final results from the older Noise Ninja plugin... in my opinion with the default settings it leaves a more 'natural' appearance to the processed images.
Of course you can tweak several functions to match your taste.
Hope this helps,