Donald S. Diefendorf, P.A.-C
Medical Physician Assistant · Baltimore, MD
Donald S. Diefendorf, P.A.-C is a medical physician assistant with a practice address in Baltimore, Maryland, and NPI 1437187002, issued on Jun 30, 2006. Check the license (Maryland C0002134, as entered in NPPES) with the Maryland board that licenses this profession; the Medicare figures below come from public CMS files.
- Name
- Donald S. Diefendorf
- Credential
- P.A.-C
- Primary taxonomy
- Medical Physician Assistant 363AM0700X
- License numbers
- C0002134 MD
MA002841L PA
Self-reported in NPPES; status is on the state search - Practice location
- 2700 Quarry Lake Dr Ste 300, Baltimore, MD 21209
- Phone
- (410) 377-8900
- Enumerated
- Jun 30, 2006
- Record last updated
- Dec 5, 2025
- Fax
- (410) 377-0576
- Medicare enrollment
- Enrolled (PECOS I20251215001595); accepts Medicare assignment
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest medical physician assistant records → All 871 in Maryland → Look up another NPI →
Also registered at 2700 Quarry Lake Dr Ste 300
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Jeremy Alter, P.T., DSCPTPhysical Therapist1487786810
- Sarah Baker, CRNPAdult Health Nurse Practitioner1861754830
- Ivona Banham, PA-CPhysician Assistant1598726978
- Audrey Bershak, PTPhysical Therapist1902188485
- Michael Bershak, PTPhysical Therapist1780702175
Verify Donald S. Diefendorf in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWhich Maryland board licenses this profession
Search for license C0002134Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
21% more Medicare Part D claims than the average medical physician assistant in 2024
1,385 Medicare Part D claims for 223 beneficiaries, against an average of 1,148 among the 23,801 providers of this specialty who prescribed in Part D. 18 claims were for opioids.
Most prescribed
- Atorvastatin Calcium98 claims
- Amlodipine Besylate87 claims
- Levothyroxine Sodium38 claims
- Pantoprazole Sodium35 claims
- Losartan Potassium32 claims
- Metoprolol Succinate32 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.
Industry payments in 2024: $551.78
27 payments; by number, the most common kind was food and beverage; the largest payer was Novo Nordisk Inc. The 16,165 providers of this specialty with any payment received $1,055.00 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
Bills Medicare through 3 group practices
- Dr Jeffrey D. Gaber And Associates, P.A.Baltimore, MD
- Phoenix Rehabilitation And Health Services IncCranberry Township, PA
- Wellspan Medical GroupHanover, PA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Donald S. Diefendorf among 871 medical physician assistant records in Maryland
Donald S. Diefendorf, P.A.-C is one of 871 medical physician assistant records with a practice address in Maryland. 73% 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 4% of them.
- NPI issued2006 · 4% of these records are older, 78% newer
- In a Medicare fileYes · 73% of these records are
- In the CMS Doctors and Clinicians fileYes · 54% of these records are
- Graduated1998 · median 2012 among the 469 with a school on file
- Record last updated2025 · 63% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 363AM0700X and a Maryland practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Medical Physician Assistant providers in Maryland
There are 871 medical physician assistant records in Maryland.
All 871 in Maryland → Every provider in Baltimore → Medical Physician Assistant nationwide →
The 8 medical physician assistant records with the nearest ZIP codes
- Chana Abrams, PA-CBaltimore, MD 212091982843157
- Albert Fuzayl, PA-CBaltimore, MD 212091548327919
- Kalpana Rayadurg, PACBaltimore, MD 212091942368501
- Dina Rechthand, PA-CBaltimore, MD 212091326480716
- Dennis Rivenburgh, PHYSICIAN ASSTISTANTBaltimore, MD 212091669454104
- Henry Wynn, PA-CBaltimore, MD 212091053353805
- Heather Dalwadi, RPA-CPikesville, MD 212081922275890
- Lisa Piastrelli, PACPikesville, MD 212081679531776
Common questions
What is Donald S. Diefendorf, P.A.-C's NPI number?
Donald S. Diefendorf, P.A.-C's National Provider Identifier (NPI) is 1437187002, issued on Jun 30, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Donald S. Diefendorf, P.A.-C located?
The NPPES record lists a practice address at 2700 Quarry Lake Dr Ste 300, Baltimore, MD, 21209. Phone: (410) 377-8900. Providers update this record themselves, so call before visiting.
How can I verify Donald S. Diefendorf, P.A.-C's license?
NPPES lists Maryland license number C0002134, as entered by the provider. Search the Maryland board that licenses this profession; the NPPES record confirms identity only.
How much does Donald S. Diefendorf, P.A.-C prescribe under Medicare Part D?
In 2024, Donald S. Diefendorf, P.A.-C had 1,385 Medicare Part D claims for 223 beneficiaries; the average among medical physician assistant prescribers was 1,148. 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.