Jah-Won Koo, M.D.
NPI 1235241837 · Internal Medicine Physician · Chicago, IL
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Jah-Won Koo, M.D. is a Internal Medicine Physician provider in Chicago, IL (NPI 1235241837).
Provider details
- NPI number
- 1235241837
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- 036-097878 (IL)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
19 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
688 Medicare services, 2024 (ranked within specialty)
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 methodology.
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 Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 254 | $131 |
| Insertion of Needle Into Vein for Collection of Blood Sample36415 | 113 | $9 |
| Annual Wellness Visit, Includes a Personalized Prevention Plan of Service (pps), Subsequent VisitG0439 | 88 | $133 |
| Visit Complexity Inherent to Evaluation and Management Associated With Medical Care Services That Serve As the Continuing Focal Point for All Needed Health Care Services And/Or With Medical Care Services That Are Part of Ongoing Care Related to a Patient'SG2211 | 77 | $17 |
| Admn Sarscov2 Vacc 1 Dose90480 | 58 | $45 |
| Administration of Influenza Virus VaccineG0008 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 57 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Atorvastatin Calcium | 244 | 72 |
| Rosuvastatin Calcium | 149 | 46 |
| Losartan Potassium | 145 | 38 |
| Amlodipine Besylate | 128 | 42 |
| Pravastatin Sodium | 84 | 27 |
| Hydrochlorothiazide | 74 | 24 |
| Metoprolol Succinate | 65 |
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-08-31
- Last updated
- 2008-02-12
Frequently asked questions
- What is Jah-Won Koo's NPI number?
- Jah-Won Koo's National Provider Identifier (NPI) is 1235241837, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Jah-Won Koo's specialty?
- Jah-Won Koo is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Jah-Won Koo located?
- Jah-Won Koo's practice location on file with NPPES is 1700 W Van Buren St, Chicago, IL 60612-3218.
- What is Jah-Won Koo's phone number?
- The practice phone number listed in the NPPES registry for Jah-Won Koo is (312) 563-2875.
- Does Jah-Won Koo accept Medicare?
- Jah-Won Koo is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Jah-Won Koo's NPI active?
- Yes — Jah-Won Koo's NPI (1235241837) is active in the NPPES registry as of the last update on 2008-02-12.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.