Nathan Charles Karp
Rheumatology Physician · Palo Alto, CA
Nathan Charles Karp is a rheumatology physician with a practice address in Palo Alto, California, and NPI 1134623556, issued on Mar 20, 2018. Check the license (California A165847, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Nathan Charles Karp
- Primary taxonomy
- Rheumatology Physician 207RR0500X
- License number
- A165847 CA
Self-reported in NPPES; status is on the state search - Practice location
- 795 EL Camino Real, Palo Alto, CA 94301
- Phone
- (650) 853-2275
- Enumerated
- Mar 20, 2018
- Record last updated
- Sep 14, 2023
- Medicare enrollment
- Enrolled (PECOS I20230927003098); accepts Medicare assignment
- Medical or professional school
- University Of California, San Francisco School Of Medicine, 2018
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest rheumatology physician records → All 926 in California → Look up another NPI →
Also registered at 795 EL Camino Real
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Hamza AbbasiInternal Medicine Physician1821545484
- Arman Abdalkhani, MDOtolaryngology Physician1356536130
- Sara AbrahamsInternal Medicine Physician1952988354
- Nana Efua Adabie, PMHNP-BCPsychiatric/Mental Health Nurse Practitioner1437647732
- Amy Adams, M.D.Dermatology Physician1679643928
- William Adams, DPMFoot & Ankle Surgery Podiatrist1447487830
Verify Nathan Charles Karp in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A165847Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
83% fewer Medicare Part D claims than the average rheumatology physician in 2024
333 Medicare Part D claims for 74 beneficiaries, against an average of 1,978 among the 6,301 providers of this specialty who prescribed in Part D. Brand-name drugs were 11% of claims.
Most prescribed
- Prednisone97 claims
- Methotrexate44 claims
- Colchicine29 claims
- Allopurinol27 claims
- Alendronate Sodium19 claims
- Mycophenolate Mofetil11 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: $48.82
2 payments; by number, the most common kind was food and beverage; the largest payer was Novartis Pharmaceuticals Corporation. The 4,486 providers of this specialty with any payment received $8,538.33 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
- Regents OF The University OF CaliforniaSan Francisco, CA
- Ucsf Medical Group Business ServicesBurlingame, CA
- University OF California San FranciscoSan Francisco, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Nathan Charles Karp among 926 rheumatology physician records in California
Nathan Charles Karp is one of 926 rheumatology physician records with a practice address in California. 81% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2018, is newer than 90% of them.
- NPI issued2018 · 90% of these records are older, 7% newer
- In a Medicare fileYes · 81% of these records are
- In the CMS Doctors and Clinicians fileYes · 69% of these records are
- Graduated2018 · median 2003 among the 641 with a school on file
- Record last updated2023 · 62% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RR0500X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Rheumatology Physician providers in California
There are 926 rheumatology physician records in California.
All 926 in California → Every provider in Palo Alto → Rheumatology Physician nationwide →
The 8 rheumatology physician records with the nearest ZIP codes
- Arthur Bobrove, M.D.Palo Alto, CA 943011356453500
- Melvin BrittonPalo Alto, CA 943011215017488
- David Fischer, MDPalo Alto, CA 943011164524229
- Poonam Manwani, M.D.Palo Alto, CA 943011609220839
- Christine Thorburn, MDPalo Alto, CA 943011659473726
- Alvina Chu, M.D.Palo Alto, CA 943041538355375
- Lorinda Chung, MDPalo Alto, CA 943041427026442
- Robert Fairchild, M.D., PH.D.Palo Alto, CA 943041255607214
Common questions
What is Nathan Charles Karp's NPI number?
Nathan Charles Karp's National Provider Identifier (NPI) is 1134623556, issued on Mar 20, 2018. An NPI identifies a provider in billing; it is not a license.
Where is Nathan Charles Karp located?
The NPPES record lists a practice address at 795 EL Camino Real, Palo Alto, CA, 94301. Phone: (650) 853-2275. Providers update this record themselves, so call before visiting.
How can I verify Nathan Charles Karp's license?
NPPES lists California license number A165847, as entered by the provider. Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Nathan Charles Karp prescribe under Medicare Part D?
In 2024, Nathan Charles Karp had 333 Medicare Part D claims for 74 beneficiaries; the average among rheumatology physician prescribers was 1,978. 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.