The present invention generally relates to the improvement of tissue health by increasing local blood flow. In some aspects of the invention, increased local blood flow is effected by the transdermal delivery of the nitric oxide precursor L-arginine and/or its derivatives alone, or optionally in conjunction with an adjunct such as theophylline. The transdermal delivery is effected, in certain embodiments through the means of a hostile biophysical environment, such as that created by a high ionic strength environment. Various pathological states caused by, or occurring in conjunction with, insufficient blood flow, can be treated using the systems and methods of the invention as described herein. In other embodiments, increased blood flow using the systems and methods of the invention may result in enhanced healing, for example, through greater availability of the constituents of the blood. Examples of conditions which may benefit from increased blood flow include, but are not limited to, erectile dysfunction, hair loss, female sexual dissatisfaction, sagging facial or other body tissue, peripheral vascular disease including claudication, neuropathy, skin ulcers, bone healing, wound healing, viral and bacterial infection, and skin grafting.