NPPES file of Aug 9, 2026

Grant Dennis Doolittle, DO

Internal Medicine Physician · Ames, IA

Grant Dennis Doolittle, DO is an internal medicine physician with a practice address in Ames, Iowa, and NPI 1457464836, issued on Aug 17, 2006. Check the license (Iowa 3721, as entered in NPPES) on the Iowa Board of Medicine; the Medicare figures below come from public CMS files.

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

NPPES recordNPPES file of Aug 9, 2026
1457464836
Name
Grant Dennis Doolittle
Credential
DO
Primary taxonomy
Internal Medicine Physician 207R00000X
License number
3721 IA
Self-reported in NPPES; status is on the state search
Practice location
1215 Duff Ave, Ames, IA 50010
Phone
(515) 239-4431
Enumerated
Aug 17, 2006
Record last updated
Nov 11, 2020 (not updated in 6 years: call before relying on the address or phone)
Fax
(515) 239-4742
Medicaid ID
1457464836 IA
Medicare enrollment
Enrolled (PECOS I20070719000182); accepts Medicare assignment
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 1215 Duff Ave

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

  1. Christopher AlbertPharmacist1811480056
  2. Jill AlexanderPediatrics Physician1851387591
  3. Rupal Amin, M.D.Internal Medicine Physician1225024995
  4. Trisha Andersen, DOAnatomic Pathology & Clinical Pathology Physician1518917947
  5. Randy Anderson, MDDiagnostic Radiology Physician1912115288
  6. Manuel Arbelaez Agudelo, MDInternal Medicine Physician1093237562

Verify Grant Dennis Doolittle in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersIowa Board of Medicine
    Search for license 3721
    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 Iowa license search

PlainDoctor does not match the HHS-OIG exclusion list to individual records: most entries carry no NPI. Search the OIG exclusion list by name.

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4.2 times the Medicare Part D claims of the average internal medicine physician in 2024

13,207 Medicare Part D claims for 886 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 9% of claims. 430 claims were for opioids.

  1. Grant Doolittle13,207
  2. Specialty average3,176

Most prescribed

  1. Atorvastatin Calcium1,135 claims
  2. Amlodipine Besylate670 claims
  3. Rosuvastatin Calcium580 claims
  4. Levothyroxine Sodium549 claims
  5. Omeprazole523 claims
  6. Losartan Potassium489 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

  1. Mcfarland Clinic PCAmes, IA

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

Grant Dennis Doolittle among 871 internal medicine physician records in Iowa

Grant Dennis Doolittle, DO is one of 871 internal medicine physician records with a practice address in Iowa. 70% 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, 62% newer
  • In a Medicare fileYes · 70% of these records are
  • In the CMS Doctors and Clinicians fileYes · 44% of these records are
  • Graduated1999 · median 2008 among the 386 with a school on file
  • Record last updated2020 · 46% 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 Iowa practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).

18 internal medicine physician records list a practice address in Ames

They are 18 of the 1,249 NPPES records with a practice address in Ames, and 871 internal medicine physician records in Iowa.

The 8 internal medicine physician records with the nearest ZIP codes

  1. Rupal Amin, M.D.Ames, IA 500101225024995
  2. Louis Banitt, MDAmes, IA 500101053544932
  3. Shauna Basener, DOAmes, IA 500101902060759
  4. Todd Berryhill, M.D.Ames, IA 500101063409563
  5. James Gohman, M.D.Ames, IA 500101942298856
  6. Jodi Goldsberry, MDAmes, IA 500101821186925
  7. Sarah Hayes, M.D.Ames, IA 500101154310209
  8. Jennifer Killion, M.D.Ames, IA 500101649269648

Common questions

What is Grant Dennis Doolittle, DO's NPI number?

Grant Dennis Doolittle, DO's National Provider Identifier (NPI) is 1457464836, issued on Aug 17, 2006. An NPI identifies a provider in billing; it is not a license.

Where is Grant Dennis Doolittle, DO located?

The NPPES record lists a practice address at 1215 Duff Ave, Ames, IA, 50010. Phone: (515) 239-4431. Providers update this record themselves, so call before visiting.

How can I verify Grant Dennis Doolittle, DO's license?

NPPES lists Iowa license number 3721, as entered by the provider. Search the Iowa Board of Medicine at https://dial.iowa.gov/about-dial/boards-and-commissions/medicine. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.

How much does Grant Dennis Doolittle, DO prescribe under Medicare Part D?

In 2024, Grant Dennis Doolittle, DO had 13,207 Medicare Part D claims for 886 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.