Faculty
You’ll be part of a community of learners led by faculty mentors who provide the highest- caliber training and treat you as a valued colleague. We’ll make sure you leave our program prepared to take the next step on your career path.

Joseph Valdez, MD
Addiction Medicine Fellowship Director
Joseph Valdez, MD, MPH, FASAM, has a medical degree from Jefferson Medical College and a master of public health degree from Johns Hopkins Bloomberg School of Public Health. Dr. Valdez completed a residency in family medicine prior to completing a fellowship in addiction medicine at Geisinger. Prior to working at Geisinger, Dr. Valdez served as the medical director for outpatient addiction medicine services at Mercy Hospital in Portland, Maine. At Mercy, Dr. Valdez oversaw integration of addiction medicine into a primary care setting in addition to inpatient consult and partial hospitalization duties. He currently works at outpatient addiction clinics for Geisinger in Bloomsburg and Wilkes-Barre, Pa., and serves as a lecturer for the American Society of Addiction Medicine. Dr. Valdez has been at the forefront of telemedicine expansion efforts at Geisinger.

Margaret Jarvis, MD, DFASAM
Margaret Jarvis, MD, DFASAM, is board-certified in addiction medicine and addiction psychiatry. She has worked at Geisinger since 1999, first as the medical director at Marworth, and currently as the chief of Addiction Medicine. She has also worked a great deal for the American Society of Addiction Medicine (ASAM) and has chaired committees and served as an officer of the board of directors. She currently chairs the ASAM Criteria Strategy Committee. Dr. Jarvis also has written for the addiction medicine examination in all its manifestations, currently in the American Board of Preventive Medicine Addiction Medicine Subcommittee.

Henry “Tripp” Dietrich, MD
Henry “Tripp” Dietrich, MD, is a board-certified physician, specializing in family medicine and addiction medicine. He obtained his medical degree from the University of Virginia and completed his residency at Mountain Area Health Education Center. Dr. Dietrich currently works at the Outpatient Addiction Medicine Clinic in Williamsport, Pa.

Kimberly Kabernagel, DO, FASAM
Kimberly Kabernagel, DO, FASAM, completed her medical education at Philadelphia College of Osteopathic Medicine. She completed residency at Wellspan York Hospital after which she obtained primary boards in family medicine. She then went on to complete her fellowship at Geisinger and is board certified in addiction medicine. Dr. Kabernagel started and developed Geisinger’s first Addiction Medicine Consult and Liaison Service. Dr. Kabernagel remained at Geisinger, beginning her current role as medical director of Geisinger Marworth Treatment Center in January 2020. Dr. Kabernagel serves on the behavioral health leadership team. She also participates in various educational events to include lecturing, completing peer review for journal articles, teaching training courses and training both residents and medical students. She serves as an associate professor of medicine at Geisinger Commonwealth School of Medicine.

Benjamin Kum, DO
Benjamin Kum, DO, is a graduate of New York Institute of Technology College of Osteopathic Medicine (2013). He completed his family medicine residency at St. John's Episcopal Hospital in Far Rockaway, N.Y., and he completed a fellowship in addiction medicine at Geisinger Marworth Treatment Center in Waverly, Pa. He is board-certified in family medicine and in addiction medicine. Dr. Kum spends his clinic time at the Outpatient Addiction Medicine Clinic in Scranton, Pa., and leads the Geisinger telehealth inpatient consult service. He is on the editorial board for the Journal of Addictive Diseases, a lecturer for the American Society of Addiction Medicine and a clinical instructor at Geisinger Commonwealth School of Medicine and for the Geisinger psychiatry residency.
