What is Susan O'Brien's background?

Dr. O'Brien has over 46 years of experience in internal medicine. Dr. O'Brien works within a group practice.

Does Susan O'Brien take Medicare?

Dr. O'Brien has a Medicare provider ID. Contact the office to confirm enrollment and other coverage.

How do I reach Susan O'Brien's office?

101 the City Drive South, Bldg. 23, Rm. 403, Orange, CA 92868. Phone: (714) 456-8000. Fax: (714) 456-3810. Virtual visits are also available for patients who prefer remote care.

How does a virtual visit with Dr. O'Brien work?

Dr. O'Brien's office sends a secure video link before your appointment. You can join from any device with a camera — phone, tablet, or laptop. Most visits take 15–30 minutes. See the telehealth section above for what to prepare.

Susan M. O'Brien, M.D.

Medical Oncology Internal Medicine

Internal Medicine

(714) 456-8000Orange, CA

Telehealth Available

NPI Active per CMS — Q2 2026

Telehealth Available NPI Active per CMS — Q2 2026

Susan O'Brien, M.D. practices as part of a group medical oncology internal medicine specialist practice in Orange, CA. She has been in practice for 46+ years. Medical oncologists diagnose and treat cancer using chemotherapy, immunotherapy, targeted therapy, and hormone therapy.

1 of 235 Internal Medicine providers in CASee all Internal Medicine in Orange|46+ years experience|NPI since 2006

Data updated 2019-06-06 on CMS NPPES

Contact & Location

Practice Location

101 the City Drive South Bldg. 23, Rm. 403, Orange, CA 92868

(714) 456-8000

Fax: (714) 456-3810

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Background & Specialty

Education, training, and specialty classification from CMS NPPES and Medicare records.

Internal Medicine Medical Oncology in OrangeAllopathic & Osteopathic Physicians

Medical oncologists diagnose and treat cancer using chemotherapy, immunotherapy, targeted therapy, and hormone therapy. They coordinate care with surgical oncologists and radiation oncologists for comprehensive cancer treatment.

Taxonomy: 207RX0202X

Virtual Medical Oncology Care With Susan O'Brien

NPPES records indicate this provider offers telehealth services. Contact the office to confirm availability and scheduling.

Schedule a virtual visit with Susan O'Brien for follow-ups, medication reviews, and ongoing care — no travel to Orange required. The office sends a secure video link before your appointment. Most visits take 15–30 minutes.

Frequently Asked Questions

Common questions about Susan O'Brien

NPI records show Dr. O'Brien as active with telehealth listed in Orange, CA. Note: NPI status alone doesn't confirm open availability — always call ahead. Phone: (714) 456-8000.

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Medical Disclaimer: NPI Telehealth is a provider directory for informational purposes only. This page does not constitute medical advice, diagnosis, or treatment recommendations. Provider data is sourced from the CMS NPPES federal registry and public Medicare datasets. NPI Telehealth does not verify clinical qualifications beyond federal records. Data may not reflect real-time availability — always contact the provider's office directly to confirm details before seeking care.

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