Allen J. Hamaker, MD
Internal Medicine Physician · Okc, OK
Allen J. Hamaker, MD is an internal medicine physician with a practice address in Okc, Oklahoma, and NPI 1326028663, issued on Jan 20, 2006. Check the license (Oklahoma 20735, as entered in NPPES) on the Oklahoma Board of Medical Licensure and Supervision; the Medicare figures below come from public CMS files.
- Name
- Allen J. Hamaker
- Credential
- MD
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- 20735 OK
Self-reported in NPPES; status is on the state search - Practice location
- 3613 NW 56TH St., Okc, OK 73112
- Phone
- (405) 949-6481
- Enumerated
- Jan 20, 2006
- Record last updated
- Oct 14, 2014 (not updated in 12 years: call before relying on the address or phone)
- Fax
- (405) 795-5908
- Medicaid ID
- 100060090A OK
- Medicare enrollment
- Enrolled (PECOS I20050603000727); accepts Medicare assignment
- Medical or professional school
- Wayne State University School Of Medicine, 1990
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 1,115 in Oklahoma → Look up another NPI →
Verify Allen J. Hamaker in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersOklahoma Board of Medical Licensure and Supervision
Search for license 20735Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
32% more Medicare Part D claims than the average internal medicine physician in 2024
4,205 Medicare Part D claims for 172 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. 346 claims were for opioids.
Most prescribed
- Rosuvastatin Calcium248 claims
- Levothyroxine Sodium147 claims
- Amlodipine Besylate121 claims
- Hydrocodone-Acetaminophen121 claims
- Atorvastatin Calcium118 claims
- Lisinopril97 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: $137.38
2 payments; by number, the most common kind was food and beverage; the largest payer was Argenx US, Inc. The 50,334 providers of this specialty with any payment received $1,303.06 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.
Allen J. Hamaker among 1,115 internal medicine physician records in Oklahoma
Allen J. Hamaker, MD is one of 1,115 internal medicine physician records with a practice address in Oklahoma. 77% 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 11% of them.
- NPI issued2006 · 11% of these records are older, 57% newer
- In a Medicare fileYes · 77% of these records are
- In the CMS Doctors and Clinicians fileYes · 59% of these records are
- Graduated1990 · median 2007 among the 653 with a school on file
- Record last updated2014 · 56% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a Oklahoma practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Internal Medicine Physician providers in Oklahoma
There are 1,115 internal medicine physician records in Oklahoma.
All 1,115 in Oklahoma → Every provider in Okc → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Jack Butler, DOOklahoma City, OK 731121316925449
- Shabbir Chaudhry Inc, M.D.Oklahoma City, OK 731121487613865
- Darlene Foster, MDOklahoma City, OK 731121194717132
- Erin Glasgow, MDOklahoma City, OK 731121780621136
- Kristopher Lepere, D.O.Oklahoma City, OK 731121568461317
- Long Nguyen, M.D.Oklahoma City, OK 731121811956006
- Neena Philip, MDOklahoma City, OK 731121346244365
- Lori Pickrell, MDOklahoma City, OK 731121104801893
Common questions
What is Allen J. Hamaker, MD's NPI number?
Allen J. Hamaker, MD's National Provider Identifier (NPI) is 1326028663, issued on Jan 20, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Allen J. Hamaker, MD located?
The NPPES record lists a practice address at 3613 NW 56TH St., Okc, OK, 73112. Phone: (405) 949-6481. Providers update this record themselves, so call before visiting.
How can I verify Allen J. Hamaker, MD's license?
NPPES lists Oklahoma license number 20735, as entered by the provider. Search the Oklahoma Board of Medical Licensure and Supervision at https://www.okmedicalboard.org/. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Allen J. Hamaker, MD prescribe under Medicare Part D?
In 2024, Allen J. Hamaker, MD had 4,205 Medicare Part D claims for 172 beneficiaries; the average among internal medicine physician prescribers was 3,176. 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.