John Christian Oneil, M.D.
General Practice Physician · Calistoga, CA
John Christian Oneil, M.D. is a general practice physician with a practice address in Calistoga, California, and NPI 1952573826, issued on Mar 31, 2008. Check the license (California A118663, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- John Christian Oneil
- Credential
- M.D.
- Primary taxonomy
- General Practice Physician 208D00000X
- License number
- A118663 CA
Self-reported in NPPES; status is on the state search - Practice location
- 3076 Myrtledale RD, Calistoga, CA 94515
- Phone
- (707) 942-6888
- Enumerated
- Mar 31, 2008
- Record last updated
- Jul 2, 2026
- Entity
- Type 1 · individual
8 nearest general practice physician records → All 1,956 in California → Look up another NPI →
Also registered at 3076 Myrtledale RD
A shared address usually means a shared clinic or building; it does not show who employs whom.
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Verify John Christian Oneil in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A118663Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
100% fewer Medicare Part D claims than the average general practice physician in 2024
13 Medicare Part D claims, against an average of 3,030 among the 8,395 providers of this specialty who prescribed in Part D.
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.
John Christian Oneil among 1,956 general practice physician records in California
John Christian Oneil, M.D. is one of 1,956 general practice physician records with a practice address in California. 48% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2008, is newer than 50% of them.
- NPI issued2008 · 50% of these records are older, 46% newer
- In a Medicare fileYes · 48% of these records are
- In the CMS Doctors and Clinicians fileNo · 27% of these records are
- Record last updated2026 · 60% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 208D00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
1 general practice physician record lists a practice address in Calistoga
They are 1 of the 45 NPPES records with a practice address in Calistoga, and 1,956 general practice physician records in California.
All 1,956 in California → Every provider in Calistoga → General Practice Physician nationwide →
The 8 general practice physician records with the nearest ZIP codes
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- Sarah Ballard, M.D.Alameda, CA 945011316092174
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- Julia Nyquist, MDAlameda, CA 945011205813771
Common questions
What is John Christian Oneil, M.D.'s NPI number?
John Christian Oneil, M.D.'s National Provider Identifier (NPI) is 1952573826, issued on Mar 31, 2008. An NPI identifies a provider in billing; it is not a license.
Where is John Christian Oneil, M.D. located?
The NPPES record lists a practice address at 3076 Myrtledale RD, Calistoga, CA, 94515. Phone: (707) 942-6888. Providers update this record themselves, so call before visiting.
How can I verify John Christian Oneil, M.D.'s license?
NPPES lists California license number A118663, 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 John Christian Oneil, M.D. prescribe under Medicare Part D?
In 2024, John Christian Oneil, M.D. had 13 Medicare Part D claims; the average among general practice physician prescribers was 3,030. 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.