Lucia:
I'm afraid I don't know about
Medicare/Medicaid, sorry. But I thought I'd chime in with a suggestion for you if you do end up getting one... My shower chair came home with me from the hospital the last time I was there. The OT gal took me to a bathroom they had that was set up like a home bathroom and showed me a couple different models that were available and we discussed which would work best for me. In particular, I needed to choose between one that fit entirely inside the tub and another that sits inside the tub but extends over the edge of the tub and has two additional legs that sit on the bathroom floor.
I ended up going with the extended model, and I'm SO, SO glad that I did (although it took me awhile to figure out how to work the shower curtain to keep from flooding the room
). Having the extra length (or width, I guess?) on the seat really helps with getting in and out of the shower - I don't have to step over the tub at all. I can just sit down and then move one leg at a time over the edge. Also, I can sit on that part of the seat while I'm drying off - which really helps a lot too.
I'm sorry I can't tell you how much it cost. It was billed as a part of my hospital charges through my insurance, so I never actually saw the itemized charge for the OT equipment I took home. If you can find one that is affordable, though, or if Medicare will cover it, I would definitely recommend that you go for the kind that extends over the edge of the tub.
Ry