Patient Portal ; Bill Pay ; Careers ... 225 Oak Springs Dr., Suite 201. Warrenton, VA 20186. View on Google Maps. Phone: 540.878.5408. Fax: 540.878.5731 ... As an internal medicine physician, Dr. Ackerman is trained to deal with whatever health problems his patients are facing—no matter how common or rare, no matter how simple or complex. And ....