I have a female friend that is 52 years old. For the past six months she has been using a dry heating pad on her right hip for three to four hours nightly.

Now her right hip is swollen and gives her moderately sever pain on her right hip
And abdomin. Even her back is swollen and tender to the touch. She has had CT scans, MRI of the abdomin with no problem being found.

I think that this swollen and tenderness is being caused by the over use of the heating pad.

Does anybody have any ideas about this right side over the hip area and her abdomin being swollen and tender to the touch?

I think her doctors are missing something.
If she isn't lying on top of the heating pad, and she isn't getting burned, then it's not serious overuse, despite the warnings that come with the pad.
I agree that dry heat isn't as good as moist (a damp washcloth).
I suggest that she see a chiropractor, one who has good referrals from others locally. Bring her scans with her.