Suggest Treatment For Intermittent Burning Sensation In Hands

I am 29 year old female and have been getting burning sensations going down my veins on the front of my hands for 11 years now? I have been to plenty of doctors and had lots of test done and they have all found nothing and have not been able to help. I have been a vegetarian for 19 years, but all of my blood work testing for deficiencies has come back normal as well. The burning pain does come and go, but if I try to use my hands for very long the pain gets too intense to continue. All of this started in college after a summer of too much writing and typing. Any ideas would be great!