One of the CAM approaches for enhancing the nitric oxide pathway is use of an amino acid named l-arginine.

The use of this amino acid is heavily promoted.
However, there are some side-effects and interactions which are very important to note.

http://www.webmd.com/vitamins-supple...ame=l-arginine

Please fully research and use caution before adding this amino acid to your regimen.

There are likely more safe methods of increasing blood flow, as mentioned by glenntaj, above.

To Our Healing,
DejaVu