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Internal Medicine

Mark Filstein, MD

Sees patients in Brooklyn, NY · New York

Summary

Mark Filstein, MD (Internal Medicine) is enrolled with Medicare at 1 practice location in Brooklyn, NY. NPI 1649396110. Medicare data says the clinician accepts Medicare assignment. Source: CMS National Downloadable File, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Mark Filstein, joined by NPI number (data updated 2026-10-02). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

At a glance

Internal MedicinePrimary specialty
YesAccepts Medicare assignment
41Years since medical school (graduated 1985)
University Of California, San Francisco School Of MedicineMedical school
MaleGender (as listed)
Mark Filstein MD PLLCGroup practice

Quick answers

Where does Mark Filstein see patients?
Medicare's clinician data lists 1 practice location in Brooklyn, NY. Call before your visit to confirm the address.
What is Mark Filstein's specialty?
Medicare lists Internal Medicine as the primary specialty.
Does Mark Filstein accept Medicare assignment?
Yes. Medicare's clinician data says Mark Filstein accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
What is the phone number for Mark Filstein?
(718) 934-6777, as listed in official Medicare / NPI Registry data.
What is Mark Filstein's NPI number?
1649396110. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Practice locations

Addresses where Mark Filstein is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Mark Filstein as a member of this group (CMS data updated 2026-10-02).

  • Mark Filstein MD PLLC2 clinicians in the group

Specialties

Find other Internal Medicine doctors in New York →

Other internal medicine doctors in Brooklyn

Clinicians with the same Medicare primary specialty in Brooklyn, NY — not a recommendation.

All internal medicine doctors in Brooklyn →

Clinician information

CredentialMD
Medical schoolUniversity Of California, San Francisco School Of Medicine
Graduation year1985
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1649396110
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  2. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  3. Medicare Care Compare — official Medicare tool to look up clinicians