The use of L-Arginine will cause diminishing returns. By this I mean that your body will most likely get used to a certain level (e.g. 1500mg capsule) over several months and you may not experience the same result. Thus, you would need to increase your dosage. I would suggest, if you've never taken L-Arginine, to buy small dosage pills - maybe 500mg to start and work your way up from there once you no longer experience the desired level of effect from 500mg.

I have spoken to many "meat heads" who use L-Arginine and they suggest to cycle on and off. For example, take a certain dosage consistently for several months and then quit taking it altogether for a month. After that month is up, start at a low dosage and work your way up again as needed. This cycling is similar in philosophy to Creatine usage (I believe - as I have never used Creatine).