What Causes Numbness And Tingling Sensation In The Fingers?

I am looking for a Geriatric Psychiatrist in the Dover Randolph succasunna area who is a medicare provider. I have been on meds for 20yrs and my medical Dr. just changed me to 100 Milligrams of Zoloft. I am having a reaction from it numb fingers and tingling. I need to have a professional monitor my meds. I would appreciate any help you can give me. Thank you