If you want to add a topical that won't cause scalp irritation, you might consider a copper peptide product, Tricomin or Folligen. Pickart claims that cu's enlarge follicles, which in turn causes them to generate new cells. On the face this results in better skin, on the head, in regrowth. Studies appear to confirm that cu's have regrowth capability. If your scalp is sensitive, and you choose to use Folligen, you might want to dilute the first bottle until your scalp can adjust. Folligen has a higher cu concentration than Tricomin does.