Moderate anemia was present in 25% and low serum iron levels in 75% of patients with severe nodulocystic acne. These findings, combined with an elevated serum ferritin level and normal transferrin saturation, indicate that the low serum iron levels and anemia are secondary to the chronic disease state of cutaneous inflammation rather than an iron-deficiency state. Successful therapy of the severe cystic acne with isotretinoin (13-cis-retinoic acid) resulted in return of serum iron and hemoglobin values to normal levels and a decrease in serum ferritin level.