... do this? Taking Humira for Scoriatic Arthritis and was also in MTX. for some yrs. Doctor stopped MTX. and put me on Humira 40 mg. pen weekly. Initially I took Humira twice a month for two years. Noticed getting weaker, and shortness of breath x 2 wks. Have been taking weekly for about 3 months? I am 70; however, this adverse reaction came on suddenly.