How long does it take for prednisone to work for psoriatic arthritis Home › Forums › General Discussion › How long does it take for prednisone to work for psoriatic arthritis This topic has 0 replies, 1 voice, and was last updated 7 years, 3 months ago by fervitonup1990. You must be logged in to reply to this topic. Log In Username: Password: Keep me signed in Log In