February 4, 2026

Tania Dempsey, MD

Board-Certified Internal Medicine Physician | MCAS & Complex Chronic Illness Specialist

Tick Boot Camp Podcast

Dr. Tania Dempsey was featured on the Tick Boot Camp Podcast:

(coming soon)

About Dr. Dempsey

Dr. Tania Dempsey, MD, is a nationally and internationally recognized physician specializing in complex chronic illness, Mast Cell Activation Syndrome (MCAS), Lyme disease, autoimmune conditions, and immune dysregulation. She is the founder of the AIM Center for Personalized Medicine in Purchase, New York, where she provides advanced, patient-centered care to individuals who have often spent years searching for answers.

Patients travel from across the United States and around the world to work with Dr. Dempsey after experiencing persistent, unexplained symptoms that conventional medicine has been unable to resolve. Her approach blends evidence-based conventional medicine with integrative and functional strategies, always focused on identifying and addressing the root causes of illness rather than masking symptoms.

A Leader in MCAS, Lyme Disease, and Multisystem Illness

Dr. Dempsey is widely regarded as one of the leading clinical experts in Mast Cell Activation Syndrome (MCAS)—a condition now recognized as a key driver of symptoms in many patients with Lyme disease, ME/CFS, autoimmune illness, mold exposure, and other chronic conditions.

She is especially known for treating patients who:

Do not tolerate standard medications or supplements
Experience symptoms across multiple organ systems
Have been told their labs are “normal” despite significant illness
Have not improved with standard Lyme disease or autoimmune protocols

Her clinical expertise spans the complex overlap of infection, immune dysfunction, hormonal imbalance, environmental exposure, and nervous system dysregulation.

Clinical Focus Areas

Dr. Dempsey regularly treats patients with:

Mast Cell Activation Syndrome (MCAS)
Lyme disease and associated co-infections (including Bartonella and Babesia)
Autoimmune and inflammatory conditions
Myalgic Encephalomyelitis / Chronic Fatigue Syndrome (ME/CFS)
Dysautonomia and POTS
Mold and environmental toxicity
Thyroid and adrenal dysfunction
Hormone imbalance
Chemical sensitivities and medication intolerance

Personalized, Integrative Approach to Care

At the AIM Center for Personalized Medicine, Dr. Dempsey takes a highly individualized approach to each patient. She views complex chronic illness as a systems-level problem, requiring careful sequencing of treatment and close collaboration between physician and patient.

Her care philosophy emphasizes:

Treating immune dysregulation before aggressive therapies
Understanding why patients react to treatments
Using low-and-slow, precision-based interventions
Educating patients so they can become informed advocates for their own health

Available treatment modalities include functional medicine, advanced diagnostics, clinical nutrition, peptide therapy, IV vitamin therapy, and IV hyperbaric (10-pass) ozone therapy when appropriate.

Education, Credentials & Affiliations

Medical Degree: Johns Hopkins University School of Medicine
Residency: Internal Medicine, NYU Medical Center / Bellevue Hospital
Board Certification: Internal Medicine
Diplomate: American Board of Integrative and Holistic Medicine (ABIHM)

Dr. Dempsey serves on the Board of Directors of ILADS (International Lyme and Associated Diseases Society) and is a faculty member of the ILADS Vector-Borne Illness Fundamentals course. She is also a founding member and Executive Board Treasurer of ISMCAS, the International Society for Mast Cell Activation Syndrome.

Her professional affiliations include:

U.S. ME/CFS Clinician Coalition
American Academy of Ozonotherapy
Institute for Functional Medicine (IFM)
American College of Physicians
International Society for the Study of Women’s Sexual Health (ISSWSH)

Research, Publications & Thought Leadership

Dr. Dempsey is a respected contributor to medical research and education in the field of complex chronic illness. Her work includes co-authoring and contributing to landmark publications such as:

Diagnosis of Mast Cell Activation Syndrome: A Global Consensus-2
Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Essentials of Diagnosis and Management (Mayo Clinic Proceedings)
Peer-reviewed research on mast-cell-targeted treatments and immune-mediated conditions

She is a frequent speaker at international medical conferences and has been featured in major media outlets including Fox 5 NY, Reader’s Digest, Huffington Post, The New York Post, and more.

Beyond the Clinic

Dr. Dempsey is deeply committed to patient education and advocacy. She co-hosts the podcast Mast Cell Matters, where she and leading experts discuss MCAS, immune dysfunction, diagnostics, and emerging treatments for complex illness.

Her passion for medicine was inspired at an early age by her grandmother, a nurse practitioner who cared for underserved communities in Eastern Europe during the mid-20th century. That legacy of compassion continues to shape Dr. Dempsey’s work today.