I'm so sorry to hear about the tendinitis. I have had it in the past. The one thing I found helpful was ice, lots and lots of ice whenever possible. I bought multiple ice packs so I could switch them as needed. (it was also easier than making ice over and over). I also wore wrist braces (bought at the store) to bed at night. It helped me from moving them and gave them a real brake. I could tell the difference between nights when I wore them and those that I didn't. When I tried anti-inflammatory for it I couldn't stay on them because they messed with my psych meds. However, they suggested that I use an antacid to see if it helped my stomach when it was made upset by them. There are also other types of anti-inflammatory like ibuprofen that you may be able to try (check w/ your doc). You may not have the same reaction to them. I second making sure you eat something when you take them.
Good Luck.