Physician Profile
Unclaimed ProfileAbout SARNAK
Based in Boston, MA, Mark J Sarnak, M.D. is listed in the NPI registry under nephrology. Mark graduated from Columbia University College of Physicians and Surgeons in 1993. According to Medicare claims data, Mark cared for 254 Medicare patients across 435 services.
Summarised automatically from public NPI registry and CMS Medicare data. Not written or reviewed by this provider. Claim this profile to replace it.
Education & Training
Areas of Expertise
Licensing & Certification
Source: NPPES NPI Registry
Contact Information
- (617) 636-5866
- Email not available
Practice Locations
750 WASHINGTON ST TUFTS- NEW ENGLAND MEDICAL CENTER
Boston, MA 02111
Procedures Most Often Billed to Medicare
435 services · 254 patients · 6 distinct codes
| Procedure | Type | Code | Services |
|---|---|---|---|
| Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes | Office visit | 99232 |
116 |
| Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more | Office visit | 99214 |
112 |
| 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' | Billing code | G2211 |
97 |
| Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes | Office visit | 99233 |
73 |
| Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes | Office visit | 99222 |
19 |
| Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes | Office visit | 99223 |
18 |
Source: CMS Medicare public data. Shows how often procedures were billed — not quality of care or patient satisfaction.
Related providers
Connections drawn from the registry and from what providers have told us. A link here is not a referral or an endorsement.
Other nephrology specialists at this location 2
Same specialty, same street address — most likely the same department or group.
Also at this address 4
Providers at the same street address. Each files their own registry entry, so a shared practice often appears under several different names.
Other nephrology specialists in Boston 8
Same specialty, same city.
More connections — 15 related providers in 2 groups
Trained at Columbia University College of Physicians and Surgeons 7
Other providers in the same specialty who trained at the same institution.
Class of 1993 at Columbia University College of Physicians and Surgeons 8
Providers who graduated from the same medical school in the same year.
Common questions
What kind of doctor is Dr. Sarnak?
Dr. Sarnak is a nephrology in Boston, MA. This is the primary taxonomy recorded against the NPI in the federal registry, listed there as “NEPHROLOGY”.
NPI registry
What is Dr. Sarnak's address?
Dr. Sarnak is listed at 750 WASHINGTON ST TUFTS- NEW ENGLAND MEDICAL CENTER, Boston, MA 02111. Addresses come from the NPI registry and can lag a move, so confirm before travelling.
NPI registry
How can I make an appointment with Dr. Sarnak?
The number on file is (617) 636-5866. Guide.md cannot book appointments or pass on messages — please call the office directly.
NPI registry
What is Dr. Sarnak's NPI number?
Dr. Sarnak's National Provider Identifier is 1982641502. It is issued by the Centers for Medicare & Medicaid Services and is unique and permanent — it does not change if they move practice.
NPI registry
Where did Dr. Sarnak train?
Dr. Sarnak attended Columbia University College of Physicians and Surgeons, graduating in 1993. This comes from the CMS National Downloadable File.
CMS public data
How long has Dr. Sarnak been practicing?
Dr. Sarnak has 33 years experience. Calculated from a graduation year of 1993, reported in the CMS National Downloadable File.
CMS public data
What procedures does Dr. Sarnak perform?
According to Medicare billing data, Dr. Sarnak the Medicare record under this individual NPI shows mainly office visits and diagnostic testing. Hospital-based physicians usually have their procedural work billed by the facility rather than under their own number, so this is a floor on their practice, not a description of it. This reflects Medicare patients only and is billing volume, not a measure of quality.
Medicare claims
Has Dr. Sarnak confirmed this information?
Not yet. This profile is built from public federal data and has not been confirmed by Dr. Sarnak. If this is you, claiming it is free.
Guide.md
Is this your profile?
Verify your identity to control how patients — and AI assistants — describe you.
Claim this profileProvider data sourced from the NPPES NPI Registry and CMS public datasets. Information is provided for reference and is not medical advice.