Individual provider

Gaurav Alreja, M.D.

Nephrology Physician Hospitalist Physician Internal Medicine Physician Medicare enrolled

Gaurav Alreja, M.D. is an Internal Medicine Physician in Merrillville, IN, registered under NPI 1639346380. This provider registers 3 separate taxonomy codes, which usually means they practise across more than one recognised specialty.

Getting there

The practice address on file is 6061 BROADWAY, Merrillville, IN 46410. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.

6061 BROADWAY, Merrillville, IN 46410 Open in Google Maps →

Credentials and Medicare

State licence
LicenceStateSpecialty
01076949A IN Nephrology Physician
01076949A IN Hospitalist Physician
IMLC.MD.70137464 WA Internal Medicine Physician
35C.003571 OH Internal Medicine Physician primary

Licences are recorded in 3 states: IN, WA, OH. Providers licensed in several states often practise near a state border or deliver telehealth across state lines.

Medicare (PECOS)
Status
Approved
Provider type
Practitioner - Nephrology
PAC ID
6204995145

Enrolled in Medicare 5 times, across 5 states:

StateEnrollment IDProvider type
Indiana I20160623000157 Practitioner - Nephrology
Illinois I20170112003387 Practitioner - Internal Medicine
Alabama I20260324000820 Practitioner - Internal Medicine
Ohio I20260403000157 Practitioner - Internal Medicine
Georgia I20260403001283 Practitioner - Internal Medicine

Medicare enrolment is recorded as approved under the provider type Practitioner - Nephrology. There are 5 separate enrolment records across 5 states (IN, IL, AL, OH, GA). Multiple enrolments usually mean the provider bills Medicare from more than one practice location, or has kept an earlier enrolment after moving. Each record carries its own enrolment ID, listed above. Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.

Licensed in 3 states

This provider holds licences in 3 states: Indiana, Ohio and Washington. The practice address on file is in Merrillville, IN, but a licence in another state usually means they see patients there too — either at a second location or by telehealth. If the address above is far from you, it is worth calling to ask whether they practise closer to where you live.

IN Indiana practice address
Licence
01076949A
Specialty
Nephrology Physician
Verify with the IN board →
OH Ohio
Licence
35C.003571
Specialty
Internal Medicine Physician
Verify with the OH board →
WA Washington
Licence
IMLC.MD.70137464
Specialty
Internal Medicine Physician
Verify with the WA board →

Licence numbers are self-reported to NPPES at registration. They do not confirm a licence is currently active, in good standing, or valid for the specialty shown — only the state board can tell you that, which is why we link to each one.

What Internal Medicine covers

A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs. NUCC Health Care Provider Taxonomy, code 207R00000X
Allopathic & Osteopathic Physicians Internal Medicine

All registered taxonomy codes

This provider registers 4 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.

CodeSpecialtyLicenceState
207RN0300X Nephrology Physician Nephrology 01076949A IN
208M00000X Hospitalist Physician 01076949A IN
207R00000X Internal Medicine Physician IMLC.MD.70137464 WA
207R00000X Internal Medicine Physician 35C.003571 OH primary

The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.

Full NPPES record

An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.

NPI1639346380 valid check digit
Entity typeIndividual (NPI-1)
Enumeration dateMay 13, 2008
Last updatedAug 11, 2026
StatusActive
Sole proprietorNo
GenderMale
CredentialM.D.
Practice address 6061 BROADWAY
Merrillville, IN 46410
(219) 884-2640
Fax (219) 884-2810
Mailing address 120 W 22ND ST STE 200
Oak Brook, IL 60523
This record was updated on Aug 11, 2026, which is recent enough that the contact details are likely still accurate.

Number check

1639346380 passes the NPI check digit test The final digit 0 matches the value computed from the first nine digits, so this is a well-formed NPI.
How the check works, step by step

Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.

Digit 8 0 8 4 0 1 6 3 9 3 4 6 3 8
Doubled? ×2 ×2 ×2 ×2 ×2 ×2 ×2
Value 8 0 8 8 0 2 6 6 9 6 4 3 3 7

Sum = 70 · next multiple of 10 = 70 · check digit = 0 · actual last digit = 0

A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.

Common questions

What is NPI number 1639346380?
NPI 1639346380 is the National Provider Identifier assigned to Gaurav Alreja, M.D. in Merrillville, IN. It is a 10-digit number issued by the Centers for Medicare & Medicaid Services and used on claims, referrals, and prescriptions to identify the provider.
What does Internal Medicine Physician cover?
A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive…
How do I contact Gaurav Alreja, M.D.?
The phone number on file with NPPES is (219) 884-2640, last updated Aug 11, 2026. Because NPPES is only updated when a provider files a change, call ahead to confirm the number and the current practice address before visiting.
Does Gaurav Alreja, M.D. accept Medicare?
This NPI has an approved Medicare enrolment in PECOS, which means the provider is enrolled to bill Medicare. Enrolment does not guarantee they are accepting new Medicare patients — verify directly with the office.
Is NPI 1639346380 a valid number?
Yes. 1639346380 passes the Luhn check digit validation that CMS uses for NPI numbers, and it resolves to an active record in the registry.
How to use this page. Everything here comes from public federal records. Tips Health does not verify quality of care, confirm that a licence is currently active, or check malpractice history, and accepts no fees for placement. A listing is not a recommendation. Verify independently before seeking care.