Carrie, I know that some things I've tried haven't worked as well for you, and once again I am not sure what the effect will be for your little one, but I am hopeful.
Johnny is about 125-130 pounds, and we worked him up to 3 Arginine pills of 2000 mg each per day. We worked him up to this over 3 weeks, so 1 pill each day the first week, 2 pills each day the second week, 3 pills each day the third week. (You can also buy arginine powder.)
The other 2 boys, being younger, weigh less, and we worked them up to 2 pills per day.
There are a gazillion brands of arginine pills on the market. The particular one we bought (because they had the highest mg per pill in the health food store we go to) was Supplement Training Systems' Pro Muscle Nitric.
We have not seen any adverse effects, except for a very slight flushing of the face that you would not notice unless you were their mother.