About
D. from Indiana University School of Medicine, graduating magna cum laude. He completed his Family Practice Residency at St. Francis Hospital and has practiced continuously in the Indianapolis and Greenwood area since 1988. His pharmacology background shaped a thoughtful, measured approach to prescribing. He draws on it to weigh medications carefully and to favor interventions that address root causes rather than suppress symptoms.
Dr. Johnstone believes the most consequential window for preventive care falls between ages 30 and 50, when people feel healthy but frequently overlook meaningful oversight. He integrates conventional allopathic medicine with nutrition, physical activity, and supplementation. He manages thyroid disorders, insulin resistance, and sex hormone imbalances, and he offers bioidentical hormone therapy when clinically appropriate. He works with a compounding pharmacy he personally evaluated for quality. Many of his patients are healthcare professionals themselves, including physicians, nurses, and pharmacists. He has maintained multi-generational patient relationships spanning more than 30 years. Outside the clinic, he tends an organic garden, raises goats and free-range chickens, plants native shrubs for wildlife, and reads deeply in Indiana history, particularly the works of James Alexander Thom.
Education & Training
Undergraduate
University of Cincinnati College of Pharmacy, RPh (graduated summa cum laude, top of class)
Medical School
Indiana University School of Medicine, M.D. (graduated magna cum laude)
Residency
Family Practice Residency, St. Francis Hospital
Conditions Treated
Who is Dr. Johnstone right for?
Dr. Johnstone is a strong fit for patients across all life stages, from children through older adults. Adults between 30 and 50 who want proactive oversight of their metabolic and hormonal health will find his approach particularly relevant. Patients managing thyroid disorders, insulin resistance, or sex hormone imbalances benefit from his integrative focus. Healthcare professionals seeking a physician who thinks carefully about prescribing often choose Dr. Johnstone. His multi-generational patient relationships reflect a practice built on long-term trust.
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Frequently Asked Questions
Dr. Johnstone specializes in thyroid disorders, insulin resistance, and sex hormone imbalances. He also manages a full range of family medicine concerns across all age groups, including preventive care, chronic disease management, and acute illness. His functional and preventive medicine background allows him to look for root causes rather than simply managing symptoms.
Yes, Dr. Johnstone offers bioidentical hormone therapy when he determines it is clinically appropriate. He works with a compounding pharmacy he personally evaluated for quality. He applies his pharmacy background to weigh the benefits and risks carefully for each individual patient.
Dr. Johnstone earned his pharmacy degree from the University of Cincinnati College of Pharmacy, graduating at the top of his class. That training shapes how he evaluates medications, supplements, and compounded therapies. He tends to prescribe deliberately and favors approaches that address underlying causes rather than suppressing symptoms.
Yes, Dr. Johnstone sees patients from pediatric through geriatric ages. He has maintained multi-generational patient relationships spanning more than 30 years. That breadth of experience allows him to manage the full arc of a family's health across decades.
Dr. Johnstone believes the most important window for preventive care falls between ages 30 and 50. During those years, people often feel healthy but overlook meaningful health monitoring. He integrates conventional medicine with nutrition, physical activity, and supplementation to address risk factors early.
Yes, Dr. Johnstone handles gynecologic and urologic care as part of his full-spectrum family medicine practice. He manages roughly 80% of his patients' healthcare needs in-house. For concerns requiring specialist expertise, he coordinates referrals directly.
D. from Indiana University School of Medicine, graduating magna cum laude. He completed his Family Practice Residency at St. Francis Hospital. Prior to medical school, he earned his pharmacy degree from the University of Cincinnati College of Pharmacy, where he graduated summa cum laude at the top of his class.
Yes, many of Dr. Johnstone's patients are healthcare professionals themselves, including physicians, nurses, and pharmacists. His depth of pharmacology and clinical knowledge, combined with his direct-care model, appeals to patients who think carefully about their own medical decisions.
Doctor profile last updated March 21, 2026