William Patrick Mazur, M.D.

Infectious Disease Internal Medicine

Internal Medicine

William Patrick Mazur is an Infectious Disease Internal Medicine specialist based in Wilmington, DE with over 30 years of clinical experience. Medicare-enrolled per CMS records and offers virtual telehealth visits.

Also practices: INTERNAL MEDICINE

(302) 320-1300Wilmington, DE
Telehealth Available
NPI Active per CMS — Q2 2026|Medicare Enrolled|Order & Refer

William Patrick Mazur, M.D. practices as part of a group infectious disease specialist practice in Wilmington, DE. With 30+ years of experience, he has been practicing in the Wilmington area. Among his Medicare patients, common conditions include hypertension, high cholesterol, and kidney disease (per CMS data).

1 of 13 Internal Medicine providers in DESee all Internal Medicine in Wilmington30+ years experienceNPI since 2011

Older · 4218dNPPES updated 2014-11-04 · verify NPI on CMS · Verify license at Delaware Board of Medical Licensure & Discipline

Contact & Location

Practice Location

1400 N Washington St, Wilmington, DE 19801-1024

Fax: (302) 320-1374
CMS Clinical Data

How Does This Doctor Compare?

Generic Rx

↑ Higher = better

20.2%

Delaware avg: 84.9 · US avg: 82.8

Lower than most doctors nationally(-62.6 pts)

How often this doctor prescribes affordable generic drugs instead of expensive brand-name ones.

Medicare Patients

41

Unique beneficiaries

Boutique practice

Prescription Recipients

99

Patients prescribed

Prescriptions Written

1,046

Total claims

Total Medicare drug cost: $3.13M

Percentile rankings compared against 134 reporting peers in Delaware.

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.

Patient Condition Panel

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 Hypertension, High Cholesterol, and Chronic Kidney Disease.

Hypertension
Higher than avg (+3%)73%

High blood pressure — a leading risk factor for heart disease and stroke

US avg: 70.2%

↑ More patients than average (+3%) — a focus area for this doctor

High Cholesterol
Lower than avg (-4%)66%

Elevated cholesterol or triglycerides that increase heart disease risk

US avg: 70.4%

↓ Fewer patients than average (-4%) — less common here

Chronic Kidney Disease
Higher than avg (+9%)39%

Gradual loss of kidney function over time, often linked to diabetes or hypertension

US avg: 29.6%

↑ More patients than average (+9%) — a focus area for this doctor

Arthritis
Lower than avg (-15%)34%

Joint inflammation causing pain, swelling, and stiffness

US avg: 49.3%

↓ Fewer patients than average (-15%) — less common here

Diabetes
Lower than avg (-2%)32%

A condition where the body cannot properly regulate blood sugar levels

US avg: 34.5%

↓ Fewer patients than average (-2%) — less common here

GeneralBehavioralNational avg

Percentage of this provider's Medicare patients diagnosed with each condition. Source: CMS Utilization Data.

Industry Payment Transparency

$15 received from industry

1 transaction reported in 2018 ·Low tier

View on CMS Open Payments →

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 2018, attributed to William Patrick Mazur's NPI.

Patient Reviews

No patient reviews yet. If you've seen William Patrick Mazur, your feedback helps other patients.

Review PolicyAll feedback is moderated before publishing. We verify reviewer identity where possible and enforce a one-review-per-provider policy. Full guidelines →

Background & Specialty

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

Career Journey
  1. 30 years in practice

    Senior practitioner

Internal MedicineInfectious Disease in WilmingtonAllopathic & Osteopathic Physicians

Infectious disease specialists diagnose and treat complex infections including HIV/AIDS, hepatitis, tuberculosis, antibiotic-resistant infections (MRSA), post-surgical infections, and travel-related illnesses. They also provide pre-travel vaccination counseling and manage infections in immunocompromised patients.

Taxonomy: 207RI0200X

Practice Footprint

Primary hospital affiliation: Acute Care Hospitals

CMS Certification Number: 490007

View hospital on Medicare Care Compare

Virtual Infectious Disease Care With William Patrick Mazur

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

Schedule a virtual visit with William Patrick Mazur for blood pressure monitoring, cholesterol management, kidney care follow-ups — no travel to Wilmington 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 Patrick Mazur

NPI records show Dr. Mazur as active with telehealth listed in Wilmington, DE. NPI status alone doesn't confirm open availability — call the office to confirm. Phone: (302) 320-1300.

Verified across 5 federal data sources

Sourced from CMS NPPES · OIG LEIE · CMS Medicare Part D · CMS Open Payments 2018 · CMS Physician Comparator. See Data Methodology.

Is this your profile?

Verify credentials, update practice details, and manage telehealth.

Claim Profile

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.

Related Providers

Infectious Disease Internal Medicine in Delaware

See all