Well, in my case, I found it to be just the opposite. This is a very personal thing, it depends on your body, your chair, your keyboard, your usage patterns, all kinds of things. There's no one source of the problem, and no one quick fix. What works for you won't work for everybody. A lot of people try to self-diagnose themselves, and will pick up a cheap set of wrist braces at a drug store and just wear those while typing.
Wrist braces can help, but they can also do even more damage.
You shouldn't wear them for too long. Sometimes doctors will prescribe that you wear them to bed, to prevent you from sleeping with your wrists all torqued out under your body with the circulation cut off. But, if you wear them for too long, your muscles will just atrophy, and your problems will get worse. There's a balance between overworking a muscle and not using it at all. Beware of keyboard pads.