NPPES file of Aug 9, 2026

Merrill Marshall Ahrens, MD

Internal Medicine Physician · Portland, OR

Merrill Marshall Ahrens, MD is an internal medicine physician with a practice address in Portland, Oregon, and NPI 1194839225, issued on Aug 18, 2006. Check the license (Oregon ORMD17736, as entered in NPPES) on the Oregon Medical Board; the Medicare figures below come from public CMS files.

Record from CMS NPPES, file of Aug 9, 2026 · Medicare files 2023 and 2024 · method · Verify with CMS →

NPPES recordNPPES file of Aug 9, 2026
1194839225
Name
Merrill Marshall Ahrens
Credential
MD
Primary taxonomy
Internal Medicine Physician 207R00000X
License number
ORMD17736 OR
Self-reported in NPPES; status is on the state search
Practice location
19500 SE Stark St, Portland, OR 97233
Phone
(503) 669-3900
Enumerated
Aug 18, 2006
Record last updated
Jul 8, 2007 (not updated in 19 years: call before relying on the address or phone)
Medicare enrollment
Enrolled (PECOS I20071218000299); accepts Medicare assignment
Medical or professional school
Northwestern University Feinberg Medical School, 1989
Telehealth
Offers telehealth (CMS)
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). Enrollment, assignment, school and telehealth: CMS Doctors and Clinicians file, Aug 2026. A record is not a license: verify it with the state board.
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Also registered at 19500 SE Stark St

A shared address usually means a shared clinic or building; it does not show who employs whom.

  1. Christopher Alaka, RPH, C.C.R.APharmacist Clinician (PhC)/ Clinical Pharmacy Specialist1083982706
  2. Nicolle AsencioFamily Nurse Practitioner1225753692
  3. Richard Babal, MANAGEROptician1295824282
  4. Thomas Beaver, M.D.Internal Medicine Physician1215019112
  5. Jennifer Bishop, MDInternal Medicine Physician1548284557
  6. Bill Blessington, MDInternal Medicine Physician1316443674

Verify Merrill Marshall Ahrens in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersOregon Medical Board
    Search for license ORMD17736
    Check the board
  3. 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
  4. 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
  5. 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Open the Oregon license search

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92% fewer Medicare Part D claims than the average internal medicine physician in 2024

268 Medicare Part D claims for 115 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D.

  1. Merrill Ahrens268
  2. Specialty average3,176

Most prescribed

  1. Atorvastatin Calcium19 claims
  2. Levothyroxine Sodium14 claims
  3. Lisinopril13 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.

The practice group's MIPS final score for 2023 (Medicare payment program): 86.2 of 100

The Merit-based Incentive Payment System score is reported for the practice group, not for one clinician alone. Four categories are weighted into the final score; the average among 454,083 clinicians with a measured score was 83.5.

  1. Qualityout of 100 · 30% of the final score95.6
  2. Costout of 100 · 30%49.3
  3. Promoting interoperabilityout of 100 · 25%99.0
  4. Improvement activities40 of 40 points · 15%100.0

Source: CMS Quality Payment Program, MIPS performance year 2023, group reporting; category weights for 2023 (qpp.cms.gov).

Bills Medicare through 3 group practices

  1. Legacy Clinics LLCPortland, OR
  2. Legacy Emanuel Hospital And Health CenterPortland, OR
  3. Legacy Good Samaritan Hospital And Medical CenterPortland, OR

Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).

889 internal medicine physician records list a practice address in Portland

They are 889 of the 42,088 NPPES records with a practice address in Portland, and 2,116 internal medicine physician records in Oregon.

Other internal medicine physician records in Oregon

  1. Charmaine Clarisse Abalos, M.D.Medford, OR1700376050
  2. Soraya Abbassian, M.D.Portland, OR1225029184
  3. Mohamed Abdel Khalek, M.DRoseburg, OR1972687390
  4. Rand AbedalweliPortland, OR1265019996
  5. Robert Abernathy, M.D.Bend, OR1063433449
  6. Rebecca Abney, D.O.Portland, OR1881984748
  7. Mohamed Aboukhashan, MDMedford, OR1932350782
  8. Allison Abraham, D.O.Portland, OR1831488444
  9. Heidi Abreu Pacheco, M.DMount Angel, OR1669691721
  10. Hennie Abrio, MDRoseburg, OR1891925129

Common questions

What is Merrill Marshall Ahrens, MD's NPI number?

Merrill Marshall Ahrens, MD's National Provider Identifier (NPI) is 1194839225, issued on Aug 18, 2006. An NPI identifies a provider in billing; it is not a license.

Where is Merrill Marshall Ahrens, MD located?

The NPPES record lists a practice address at 19500 SE Stark St, Portland, OR, 97233. Phone: (503) 669-3900. Providers update this record themselves, so call before visiting.

How can I verify Merrill Marshall Ahrens, MD's license?

NPPES lists Oregon license number ORMD17736, as entered by the provider. Search the Oregon Medical Board at https://www.oregon.gov/OMB/Pages/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.

How much does Merrill Marshall Ahrens, MD prescribe under Medicare Part D?

In 2024, Merrill Marshall Ahrens, MD had 268 Medicare Part D claims for 115 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.

What is Merrill Marshall Ahrens, MD's MIPS final score?

The 2023 MIPS final score is 86.2 of 100, reported for the practice group. The average among 454,083 clinicians with a measured score was 83.5.

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.