Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of October 4, 2026.
NPIDirectory

Alan S Gellerstein, MD

Individual provider Family Medicine Physician · NPI 1588695712

Alan S Gellerstein, MD is registered under Family Practice in Cedar Knolls, New Jersey. Graduated from Eastern Virginia Medical School in 1996, 30 years ago. Practices with Practice Associates Medical Group, a 1,403-clinician group, accepts Medicare assignment and offers telehealth. Licensed in New Jersey.

Years since qualifying
30
Trained at
Eastern Virginia Medical School
Licensed in
NJ
In the registry since
2006
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

See every abbreviation used in this directory →

Claim this listing Report a problem Suggest an edit

Practice location Address checks out

11 Saddle Rd
Cedar Knolls, NJ 07927-1901 Not confirmed with CMS for 14 years — call before visiting
Phone: (973) 267-2122
Fax: (973) 292-1466
Show map & directions

Directions in Google Maps · Apple Maps · OpenStreetMap

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Family Medicine Physician (primary) Taxonomy 207Q00000X · Licence 25MA06879300 (NJ)

Record details

NPI number1588695712
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedJuly 5, 2006
Last updated in NPPESJune 12, 2012

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyFAMILY PRACTICE
Medical schoolEASTERN VIRGINIA MEDICAL SCHOOL
Graduated 1996 (30 years in practice)
Group practice Practice Associates Medical Group — 1403 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services
Practice locations2 on file with Medicare

Procedures

From CMS Care Compare, which counts the procedures a clinician billed to Original Medicare and Medicare Advantage over a recent 12-month period. CMS reports a fixed list of common procedures, so this is not everything the clinician does. Counts of 10 or fewer are given as a range, because CMS withholds small numbers.

Removal of skin lesions 40 times · 70th percentile
Removal of tissue 1–10 times

The percentile compares how often this clinician performed the procedure with other clinicians who performed it, as CMS calculates it. It measures volume, not outcomes or skill.

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients495
Services billed 3,521 a service is one billed item, such as a visit, a test or a procedure
Average patient age76

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Payments from drug and device companies, 2025

Drug and device makers are required by federal law (the Physician Payments Sunshine Act) to report what they pay or give to clinicians, and CMS publishes the reports as Open Payments. This is the 2025 program year. A report is a record of a payment, not an allegation of anything, and many are small items such as meals. Only general payments are listed here; research payments and ownership or investment interests are reported separately by CMS and are not shown.

Food and Beverage $1,563 126 payments · a meal or drink at a meeting or visit, not a fee

Each amount is the sum of what companies reported for that kind of payment in 2025, rounded to the dollar. Not all of it is income to the clinician: a meal is not a fee, a charitable contribution goes to a charity, and a royalty or an acquisition payment is not a salary.

Check a report, or dispute one, at the source in CMS’s own tool, Open Payments. Corrections go through CMS’s dispute process. This site removes a home address on request and asks for no proof, because that is privacy; it will not remove an accurate payment report on request, because that is a statutory public disclosure.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician. Those with a page here are linked.

  • Ahs Hospital Corp Hospital · Hackettstown, NJ
  • Morristown Medical Center Hospital · Morristown, NJ
  • Overlook Medical Center Hospital · Summit, NJ
  • Atlantic Visiting Nurse Home health agency · Morristown, NJ
  • Atlantic Visiting Nurse Hospice · Morristown, NJ

Also affiliated with 1 inpatient rehabilitation facility, which CMS identifies by certification number only.

Colleagues at Practice Associates Medical Group

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 1403 clinicians in the practice; 12 are shown here.

Other providers in Cedar Knolls