Board Certifications

  • Internal Medicine
  • Endocrinology, Diabetes, and Metabolism

Areas of Expertise

  • Diabetes
  • Osteoporosis
  • Thyroid Disorders



University of Maryland Medical Center
Endocrinology, Diabetes, and Metabolism
Baltimore, MD

Internship and Residency

University of Maryland Medical Center
Internal Medicine
Baltimore, MD
1989 and 1991

Medical School

Medical University of South Carolina
Doctor of Medicine
Charleston, SC

Undergraduate School

College of Charleston
Bachelor of Science
Charleston, SC

Hospitals Affiliated With

Greater Baltimore Medical Center
University of Maryland St. Joseph Medical Center

Professional Association

American Association of Clinical Endocrinologists


Dr. Joanna Tyzack is a senior partner at Bay West Endocrinology. She has been in practice at Bay West for over 25 years. She went to medical school in South Carolina, graduating from MUSC. She moved to Baltimore for further training and did her internship, residency and endocrinology fellowship at the University of Maryland Medical School.

Dr. Tyzack has a particular interest in the personalized management of diabetes, osteoporosis and thyroid disorders. She is a member of the American Association of Endocrinologists. She was named in Baltimore magazine as a top doctor for women in an edition dedicated to women’s health care.  

She has participated in endocrinology research both as a fellow in training and at Bay West through our close association with MODEL Clinical Research.  Most recently, she has participated in a study of an implanted continuous glucose monitor.

Dr. Tyzack is originally from England. She was born in London and came to the US with her family for her father’s work as a professor of fine art at the University of Iowa. After living in Iowa for a few years, the family relocated to Charleston, SC. She now lives in Towson, MD with her husband and dog, Charley. In her free time, she enjoys spending time with her family including two granddaughters, supporting her favorite soccer team, reading, hiking and kayaking.