Dr. Johnson completed her veterinary degree at the New York State College of Veterinary Medicine at Cornell University in 1991. She completed an internship at the Santa Cruz Veterinary hospital in California in 1992. After a few years doing general practice, teaching anatomy at a veterinary school, and completing a research project, she entered a residency program at Tufts University in the study of Emergency Medicine and Critical Care. She became board certified in this specialty in 1997.

Dr. Johnson has published several articles and textbook chapters in the topics of head trauma, nosocomial infections, and pain management. She has also lectured to veterinarians and technicians at regional veterinary conferences. She is an active member of the American College of Veterinary Emergency and Critical Care. She is the director of the internship and residency programs at OSVS.

Dr. Johnson enjoys riding her horse, planting (but not weeding) her garden, scuba diving, and other outdoorsy stuff. Most of all she loves spending time with (but not cleaning up after) her husband (Dr. Gary Block of OSVS), two amazing children, and a menagerie of pets that includes horses, goats, dogs, cats, tortoises, and about 60,000 honeybees.