Chimezie D. Ubbaonu, MD
Hematology & Oncology Physician · Vacaville, CA
Chimezie D. Ubbaonu, MD is a hematology & oncology physician with a practice address in Vacaville, California, and NPI 1790004943, issued on May 27, 2010. Check the license (California A132171, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Chimezie D. Ubbaonu
- Credential
- MD
- Primary taxonomy
- Hematology & Oncology Physician 207RH0003X
- License number
- A132171 CA
Self-reported in NPPES; status is on the state search - Practice location
- 1 Quality Dr, Vacaville, CA 95688
- Phone
- (707) 624-4000
- Enumerated
- May 27, 2010
- Record last updated
- Mar 22, 2024
- Medicare enrollment
- Enrolled (PECOS I20150619002384); accepts Medicare assignment
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest hematology & oncology physician records → All 1,583 in California → Look up another NPI →
Also registered at 1 Quality Dr
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Hydee Abaya Ghazaleh, M.D.Internal Medicine Physician1922688464
- Jonathan Abaya Ghazaleh, MDInternal Medicine Physician1093395535
- Huma Ahmad, D.O.Hospitalist Physician1154587616
- Azim Ahmady, MDFamily Medicine Physician1417035916
- Lamia Alazzawi, PHARM.D.Pharmacist1407380645
- Delaine Alejandro, DOFamily Medicine Physician1487816294
Verify Chimezie D. Ubbaonu in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A132171Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
19% fewer Medicare Part D claims than the average hematology & oncology physician in 2024
709 Medicare Part D claims for 149 beneficiaries, against an average of 877 among the 10,784 providers of this specialty who prescribed in Part D. Brand-name drugs were 8% of claims. 62 claims were for opioids.
Most prescribed
- Prochlorperazine Maleate93 claims
- Abiraterone Acetate69 claims
- Dexamethasone57 claims
- Prednisone56 claims
- Compro50 claims
- Ondansetron Hcl46 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.
Bills Medicare through one group practice
- Permanente Medical Group IncVallejo, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Chimezie D. Ubbaonu among 1,583 hematology & oncology physician records in California
Chimezie D. Ubbaonu, MD is one of 1,583 hematology & oncology physician records with a practice address in California. 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 2010, is newer than 70% of them.
- NPI issued2010 · 70% of these records are older, 28% newer
- In a Medicare fileYes · 83% of these records are
- In the CMS Doctors and Clinicians fileYes · 71% of these records are
- Graduated2003 · median 2003 among the 1,124 with a school on file
- Record last updated2024 · 58% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RH0003X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Hematology & Oncology Physician providers in California
There are 1,583 hematology & oncology physician records in California.
All 1,583 in California → Every provider in Vacaville → Hematology & Oncology Physician nationwide →
The 8 hematology & oncology physician records with the nearest ZIP codes
- Tyler Kang, M.D.Vacaville, CA 956871164691820
- James Long, M.D.Vacaville, CA 956871194821868
- Brian Vikstrom, M.D.Vacaville, CA 956871285730820
- Ernest Lo, MDCameron Park, CA 956821538482328
- Rashmi Ramasubbaiah, MDCameron Park, CA 956821326202540
- Tsuong Tsai, MDCameron Park, CA 956821851462055
- Alborz Alali, M.D.Woodland, CA 956951265458640
- Sanaz Ghafouri, M.D.Woodland, CA 956951730543539
Common questions
What is Chimezie D. Ubbaonu, MD's NPI number?
Chimezie D. Ubbaonu, MD's National Provider Identifier (NPI) is 1790004943, issued on May 27, 2010. An NPI identifies a provider in billing; it is not a license.
Where is Chimezie D. Ubbaonu, MD located?
The NPPES record lists a practice address at 1 Quality Dr, Vacaville, CA, 95688. Phone: (707) 624-4000. Providers update this record themselves, so call before visiting.
How can I verify Chimezie D. Ubbaonu, MD's license?
NPPES lists California license number A132171, 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 Chimezie D. Ubbaonu, MD prescribe under Medicare Part D?
In 2024, Chimezie D. Ubbaonu, MD had 709 Medicare Part D claims for 149 beneficiaries; the average among hematology & oncology physician prescribers was 877. 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.