Our Providers

Learn More About Southern Internal Medicine

Get the attentive care you deserve at Southern Internal Medicine in Lake City, FL. We accept new patients, 16 years old and older. We have more than 50 years of combined experience.

Our Team

Dr. Guy S. Strauss, D.O., F.A.C.O.I.

Dr. Strauss has been practicing since 1987 and is board-certified in internal medicine. With a passion for continuing medical education in order to provide the most up-to-date care for his patients, Dr. Strauss has received the American Medical Association's Physician Recognition Award a total of seven times. He has also served as a trainer and mentor for the Medical College at the University of Florida and on numerous committees for Lake City Medical Center and Shands at Lake Shore Hospital to help improve the quality of medical care in our community. Dr. Strauss is actively involved in numerous research protocols on the cutting edge of modern medicine to Dr. Strauss, as the medical director for Multi-Specialty Research Associates, is actively involved in numerous research protocols.

Dr. Stefanie Jackson, DNP, APRN

After graduating from Florida State University in 1995 as an ARNP, Stefanie began her career with Dr. Strauss. She has a loyal patient following and has developed an excellent reputation because she enjoys providing exceptional care to the residents of Columbia County and the surrounding areas. A lifelong resident of Lake City, when Stefanie is not at work, she stays busy with her husband and three children as they have many family activities.

Stefanie went on to get her doctorate in Nursing Practice at Florida State University in 2019.

Dr. Samantha Smythe,

DNP, APRN

Dr. Samantha Smythe recently joined Southern Internal Medicine in 2019 after graduating from Florida State University’s Doctoral Family Nurse Practitioner program. Samantha’s nursing career began nearly 20 years ago and her passion for helping people has been the driving force in the continual advancement of her education over the years. With a diverse nursing career background including multiple degrees in nursing, Samantha determined primary care was her passion. Her goal is to ensure patients receive quality care to enhance the level of disease prevention and progression in her community. When she isn’t working, Samantha enjoys spending time with her husband Patrick, their families, and their two pets.

Brittaney Howell, APRN

Brittaney joined Southern Internal Medicine in 2022. Brittaney graduated from Kaiser University in Tampa as an RN. She worked for UF Health Shands for 5 years on both medical and surgical services as well as emergency services. She then went on to Chamberlain University and received her master's degree in 2022 to become a Family Nurse Practitioner. Providing quality Primary Care and being able to follow the entire healthcare journey of her patients is a passion of Brittaney's. When not at work, Brittaney enjoys family time, going to Gator football games, and wilderness hiking.

Elaina Williamson, APRN

Elaina obtained her BSN from the University of Central Florida and then her MSN from the University of South Alabama. She has 10 years of experience working in the ICU and holds a critical care certification. Elaina is passionate about delivering adequate and compassionate care for her patients. When she’s away from work, Elaina enjoys traveling with her husband, Justin, and their two daughters.