Mark A. Weiss, MD
Medical Oncology Physician · Philadelphia, PA
Mark A. Weiss, MD is a medical oncology physician with a practice address in Philadelphia, Pennsylvania, and NPI 1699857508, issued on Oct 19, 2006. Check the license (Pennsylvania MD438863, as entered in NPPES) on the Pennsylvania Department of State (PALS); the Medicare figures below come from public CMS files.
- Name
- Mark A. Weiss
- Credential
- MD
- Primary taxonomy
- Medical Oncology Physician 207RX0202X
- License number
- MD438863 PA
Self-reported in NPPES; status is on the state search - Practice location
- 925 Chestnut St, Philadelphia, PA 19107
- Phone
- (215) 955-8874
- Enumerated
- Oct 19, 2006
- Record last updated
- Oct 6, 2011 (not updated in 15 years: call before relying on the address or phone)
- Fax
- (215) 955-2340
- Medicaid IDs
- 0221481 NJ
102416864 PA - Entity
- Type 1 · individual
8 nearest medical oncology physician records → All 265 in Pennsylvania → Look up another NPI →
Also registered at 925 Chestnut St
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Maysa Abu-Khalaf, MDMedical Oncology Physician1194713495
- Asim AhmedStudent in an Organized Health Care Education/Training Program1669319059
- Seyfettin Alpdogan, MDMedical Oncology Physician1558538991
- Anjali Avadhani, MDHematology & Oncology Physician1194887059
- Rita Axelrod, M.D.Medical Oncology Physician1881616126
- Donald Beahm, MDOtolaryngology Physician1245423714
Verify Mark A. Weiss in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersPennsylvania Department of State (PALS)
Search for license MD438863Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
97% fewer Medicare Part D claims than the average medical oncology physician in 2024
19 Medicare Part D claims, against an average of 703 among the 4,230 providers of this specialty who prescribed in Part D.
Most prescribed
- Brimonidine Tartrate-Timolol15 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
Mark A. Weiss among 265 medical oncology physician records in Pennsylvania
Mark A. Weiss, MD is one of 265 medical oncology physician records with a practice address in Pennsylvania. 83% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2006, is newer than 8% of them.
- NPI issued2006 · 8% of these records are older, 49% newer
- In a Medicare fileYes · 83% of these records are
- In the CMS Doctors and Clinicians fileNo · 71% of these records are
- Record last updated2011 · 68% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RX0202X and a Pennsylvania practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Medical Oncology Physician providers in Pennsylvania
There are 265 medical oncology physician records in Pennsylvania.
All 265 in Pennsylvania → Every provider in Philadelphia → Medical Oncology Physician nationwide →
The 8 medical oncology physician records with the nearest ZIP codes
- Maysa Abu-Khalaf, MDPhiladelphia, PA 191071194713495
- Rita Axelrod, M.D.Philadelphia, PA 191071881616126
- David Berd, M.D.Philadelphia, PA 191071861414195
- Emmanuel Besa, M.D.Philadelphia, PA 191071114947967
- Barbara Campling, MDPhiladelphia, PA 191071508807983
- Matthew Carabasi, M.D.Philadelphia, PA 191071255351003
- Brian Carr, MDPhiladelphia, PA 191071831161785
- Joanne Filicko-O'Hara, M.D.Philadelphia, PA 191071801818141
Common questions
What is Mark A. Weiss, MD's NPI number?
Mark A. Weiss, MD's National Provider Identifier (NPI) is 1699857508, issued on Oct 19, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Mark A. Weiss, MD located?
The NPPES record lists a practice address at 925 Chestnut St, Philadelphia, PA, 19107. Phone: (215) 955-8874. Providers update this record themselves, so call before visiting.
How can I verify Mark A. Weiss, MD's license?
NPPES lists Pennsylvania license number MD438863, as entered by the provider. Search the Pennsylvania Department of State (PALS) at https://www.pals.pa.gov/. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Mark A. Weiss, MD prescribe under Medicare Part D?
In 2024, Mark A. Weiss, MD had 19 Medicare Part D claims; the average among medical oncology physician prescribers was 703. Part D covers Medicare prescriptions only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.