William K Oh, M.D.
Medical Oncology Internal Medicine
William K Oh is a Medical Oncology Internal Medicine specialist based in Greenwich, CT with over 34 years of clinical experience. Medicare-enrolled per CMS records and offers virtual telehealth visits.
William K Oh, M.D. has practiced internal medicine for 34+ years, working in independent practice. He graduated from New York University School of Medicine in 1992 and has 34+ years of clinical experience. He regularly sees Medicare patients with high cholesterol, cancer, and hypertension (per CMS claims data).
Older · 528dNPPES updated 2024-12-11 · verify NPI on CMS · Verify license at Connecticut Medical Examining Board
How Does This Doctor Compare?
Generic Rx
↑ Higher = better79.1%
Connecticut avg: 81.1 · US avg: 82.8
⚠ Lower than most doctors nationally(-3.7 pts)
How often this doctor prescribes affordable generic drugs instead of expensive brand-name ones.
Medicare Patients
152
Unique beneficiaries
Standard volumePrescription Recipients
42
Patients prescribed
Prescriptions Written
177
Total claims
Total Medicare drug cost: $286k
Percentile rankings compared against 1,825 reporting peers in Connecticut.
Data Note: Sourced from CMS Medicare Provider Utilization & Payment Data. Percentile rankings compare this provider against all peers with reported data in the same state. Updated annually to reflect the latest federal reporting cycle.
What This Doctor Treats Most
Based on Medicare claims data — here's what patients commonly see this doctor for
Based on Medicare data, this doctor primarily manages High Cholesterol, Cancer, and Hypertension.
Elevated cholesterol or triglycerides that increase heart disease risk
US avg: 70.4%↑ More patients than average (+5%) — a focus area for this doctor
Diseases involving abnormal cell growth with potential to spread to other body parts
US avg: 20.8%↑ More patients than average (+54%) — a focus area for this doctor
High blood pressure — a leading risk factor for heart disease and stroke
US avg: 70.2%↓ Fewer patients than average (-3%) — less common here
Reduced blood flow to the heart muscle, commonly known as coronary artery disease
US avg: 31.7%↑ More patients than average (+11%) — a focus area for this doctor
Joint inflammation causing pain, swelling, and stiffness
US avg: 49.3%↓ Fewer patients than average (-8%) — less common here
A condition where the body cannot properly regulate blood sugar levels
US avg: 34.5%↓ Fewer patients than average (-3%) — less common here
Gradual loss of kidney function over time, often linked to diabetes or hypertension
US avg: 29.6%↓ Fewer patients than average (-8%) — less common here
An irregular, often rapid heartbeat that increases the risk of stroke
US avg: 22%↓ Fewer patients than average (-2%) — less common here
Percentage of this provider's Medicare patients diagnosed with each condition. Source: CMS Utilization Data.
$27.5k received from industry
13 transactions reported in 2024 ·Very High tier
Payments include consulting fees, speaking honoraria, food & beverage, travel, research support, and ownership interests from drug and medical device manufacturers. Disclosure is required by the federal Physician Payments Sunshine Act. These payments do not necessarily indicate conflicts of interest. National median: $338 across 136 000 tracked providers.
Tiers — Low: under $500 · Moderate: $500-5 000 · High: $5 000-25 000 · Very High: $25 000+. Source: CMS Open Payments 2024, attributed to William K Oh's NPI.
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Background & Specialty
Education, training, and specialty classification from CMS NPPES and Medicare records.
Graduated medical school · 1992
Nyu Grossman School of Medicine
Board certified · Dec 10, 2024
Self-reported via NPPES
34 years in practice
Senior practitioner
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
Education & Training
New York University School of Medicine (Class of 1992)
Mailing address
333 Cedar Street Po Box 208028, New Haven, CT 06520
Differs from practice location
Primary hospital affiliation: Acute Care Hospitals
CMS Certification Number: 450669
View hospital on Medicare Care CompareVirtual Medical Oncology Care With William K Oh
NPPES records indicate this provider offers telehealth services. Contact the office to confirm availability and scheduling.
Schedule a virtual visit with William K Oh for cholesterol management, follow-up consultations, blood pressure monitoring — no travel to Greenwich required. The office sends a secure video link before your appointment. Most visits take 15–30 minutes. Medicare enrolled per CMS records.
Frequently Asked Questions
Common questions about William K Oh
Dr. Oh is listed as active in the NPI registry with telehealth listed in Greenwich, CT. NPI status alone doesn't confirm open availability — call the office to confirm. Phone: (203) 863-3700.
Sourced from CMS NPPES · OIG LEIE · CMS Medicare Part D · CMS Open Payments 2024 · CMS Physician Comparator. See Data Methodology.
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Contact William K Oh
Practice Location
77 Lafayette Pl, Greenwich, CT 06830-5437
Mailing Address
333 Cedar Street Po Box 208028, New Haven, CT 06520
This is a provider directory. Contact the office directly to schedule appointments.
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