Esther Sy, MD
NPI 1659358703 · Family Medicine Physician · Rockford, IL
Enrolled with Medicare as Practitioner - Family Practice · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Esther Sy, MD is a Family Medicine Physician provider in Rockford, IL (NPI 1659358703).
Provider details
- NPI number
- 1659358703
- Entity type
- Individual
- Primary specialty
- Family Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Female
- Sole proprietor
- No
- License
- 036097622 (IL)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Ambulatory Health Care Facilities
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
20 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
2 documented practice locations
- Medicare service volume (vs. specialty peers)25% of score
111 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our .
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 70 | $64 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 41 | $94 |
Typical Medicare-allowed amounts for these services range $64–$94 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, not a price quote and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 9 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Prednisone | 91 | 88 |
| Cephalexin | 90 | 89 |
| Doxycycline Hyclate | 68 | 68 |
| Azithromycin | 43 | 43 |
| Albuterol Sulfatebrand: Albuterol Sulfate Hfa | 27 | 27 |
| Amoxicillin/Potassium Clavbrand: Amoxicillin-Clavulanate Potass | 26 | 26 |
| Sulfamethoxazole/Trimethoprimbrand: Sulfamethoxazole-Trimethoprim |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$47 across 1 record (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Additional practice locations (1)
- 3775 N Mulford RdRockford, IL 61114-5632Phone: (779) 696-9202
Registry dates
- Enumerated
- 2005-12-29
- Last updated
- 2026-04-22
- Certified
- 2026-04-22
Frequently asked questions
- What is Esther Sy's NPI number?
- Esther Sy's National Provider Identifier (NPI) is 1659358703, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Esther Sy's specialty?
- Esther Sy is listed in the NPPES registry with a primary specialty of Family Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Esther Sy located?
- Esther Sy's practice location on file with NPPES is 3401 N Perryville Rd, Rockford, IL 61114-8011.
- What is Esther Sy's phone number?
- The practice phone number listed in the NPPES registry for Esther Sy is (815) 971-2000.
- Does Esther Sy accept Medicare?
- Esther Sy is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Esther Sy's NPI active?
- Yes — Esther Sy's NPI (1659358703) is active in the NPPES registry as of the last update on 2026-04-22.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.