I haven't had any side effects except for some minor lab abnormalities. It isn't clear that Actemra (tocilizumab) is causing the lab abnormalities.

There are potential side effects to all medications.
https://www.mayoclinic.org/drugs-supplements/tocilizumab-intravenous-route-subcutaneous-route/side-effects/drg-20073821?p=1
People with certain pre-existing conditions shouldn't be prescribed Actemra. For example, Actemra should not be prescribed to anyone with a history of diverticulitis. Actemra may cause serious stomach and bowel problems, especially if you have a history of ulcers or diverticulosis.

There is also a risk of serious infections since Actemra affects the immune system. Prednisone also increases our risk of infections. I would say I've had fewer infections on Actemra compared to when I was taking prednisone.

Several other side effects have improved after I got off prednisone. I have stopped several additional medications which were used to treat prednisone side effects.

I tolerate Actemra well but some people will have side effects. I don't want to suggest that Actemra won't cause any side effects.

Actemra may not work for everyone. Maybe I just got lucky. After 12 years of PMR, prednisone and bad luck, I was overdue to have some good luck.