Oana Klein, MD
Internal Medicine Physician · Larkspur, CA
Oana Klein, MD is an internal medicine physician with a practice address in Larkspur, California, and NPI 1427240647, issued on Aug 11, 2007. Check the license (California C54895, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Oana Klein
- Credential
- MD
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License numbers
- C54895 CA
036-119158 IL
Self-reported in NPPES; status is on the state search - Practice location
- 5 Bon Air RD Ste 117, Larkspur, CA 94939
- Phone
- (415) 448-1500
- Enumerated
- Aug 11, 2007
- Entity
- Type 1 · individual
Also registered at 5 Bon Air RD Ste 117
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Alaric Akashi, MDInternal Medicine Physician1285784264
- Dylan Bellavance, DOFamily Medicine Physician1013414507
- Mykaela PoePhysician Assistant1861357147
Verify Oana Klein in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license C54895Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS, AOA, NCCPA, AANPNot checked
58% fewer Medicare Part D claims than the average internal medicine physician in 2024
1,164 Medicare Part D claims for 147 beneficiaries, against an average of 2,785 among the 127,794 providers of this specialty who prescribed in Part D. 13 claims were for opioids.
Most prescribed
- Atorvastatin Calcium128 claims
- Levothyroxine Sodium85 claims
- Amlodipine Besylate62 claims
- Losartan Potassium46 claims
- Metformin Hcl44 claims
- Gabapentin30 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: $24.62
1 payment, mostly food and beverage; the largest payer was Novo Nordisk Inc. The 65,274 providers of this specialty with any payment received $2,536.66 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.
13 internal medicine physician records list a Larkspur practice address
They are 13 of the 291 NPPES records with a Larkspur practice address, and 20,403 internal medicine physician records in California.
All 13 in Larkspur → All 20,403 in California → Every provider in Larkspur →
Other internal medicine physician records in California
- Jacob Aaron, MDSan Francisco, CA1407202518
- Alistair Aaronson, MDStanford, CA1457628760
- Jose Abad., MDSacramento, CA1144607219
- Donna Abare, MDOakland, CA1386722155
- Marce AbareScotts Valley, CA1457744708
- Samuel Abarte, M.D.Chula Vista, CA1578535498
- Alexander Abary, MDLong Beach, CA1104995919
- Luba Abascal, MDSan Francisco, CA1023180874
- Michael Abate, MDSacramento, CA1548248131
- Wali Abawi, D.O.Joshua Tree, CA1104362268
Common questions
What is Oana Klein, MD's NPI number?
Oana Klein, MD's National Provider Identifier (NPI) is 1427240647, issued on Aug 11, 2007. An NPI identifies a provider in billing; it is not a license.
Where is Oana Klein, MD located?
The NPPES record lists a practice address at 5 Bon Air RD Ste 117, Larkspur, CA, 94939. Phone: (415) 448-1500. Providers update this record themselves, so call before visiting.
How can I verify Oana Klein, MD's license?
NPPES lists California license number C54895, 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 Oana Klein, MD prescribe under Medicare Part D?
In 2024, Oana Klein, MD had 1,164 Medicare Part D claims for 147 beneficiaries; the average among internal medicine physician prescribers was 2,785. Part D covers Medicare prescriptions only.
Source: CMS National Plan and Provider Enumeration System (NPPES), loaded Aug 27, 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.
Every figure on PlainDoctor is rendered directly from the federal CMS NPPES registry, Medicare Part D, MIPS, and Open Payments records, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 27, 2026.