I have tendonitis in my left elbow. It comes and goes. It seems to stay at bay if I work my forearms more, especially reverse wrist curls. Dont try to use a lot of weight doing this, just enough you can do about 10-15 reps.
Also, make sure you really warm up your arms before you start your workout. If I just jump in and go my elbows will end up hurting. Take time to warm up with 3-5 light sets to pump blood into the tricep. Good luck!!