Thomas Mark Johnson, M.D.
Cardiovascular Disease Physician · Dubuque, IA
Thomas Mark Johnson, M.D. is a cardiovascular disease physician with a practice address in Dubuque, Iowa, and NPI 1801848486, issued on May 16, 2006. Check the license (Iowa 21505, as entered in NPPES) on the Iowa Board of Medicine; the Medicare figures below come from public CMS files.
- Name
- Thomas Mark Johnson
- Credential
- M.D.
- Primary taxonomy
- Cardiovascular Disease Physician 207RC0000X
- License numbers
- 21505 IA
29644 WI
Self-reported in NPPES; status is on the state search - Practice location
- 1000 Langworthy St, Dubuque, IA 52001
- Phone
- (563) 584-3425
- Enumerated
- May 16, 2006
- Record last updated
- Nov 25, 2009 (not updated in 17 years: call before relying on the address or phone)
- Fax
- (563) 584-3497
- Medicaid ID
- 0160531 IA
- Medicare enrollment
- Enrolled (PECOS I20100305000461); accepts Medicare assignment
- Medical or professional school
- University Of Iowa, Rj & L Carver College Of Medicine, 1974
- Entity
- Type 1 · individual
8 nearest cardiovascular disease physician records → All 169 in Iowa → Look up another NPI →
Also registered at 1000 Langworthy St
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Louis Alt, M.D.Otolaryngology Physician1902855778
- Courtney Ambrosy, PA-CPhysician Assistant1457121345
- Sarah ArnoldMedical Physician Assistant1558016113
- Paula Aston, MDNeurology Physician1144286675
- Kala Ave-Lallemant, FNPFamily Nurse Practitioner1235551656
- Martin Bagby, DOFamily Medicine Physician1942269402
Verify Thomas Mark Johnson in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersIowa Board of Medicine
Search for license 21505Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
3% fewer Medicare Part D claims than the average cardiovascular disease physician in 2024
2,993 Medicare Part D claims for 438 beneficiaries, against an average of 3,078 among the 20,728 providers of this specialty who prescribed in Part D. Brand-name drugs were 20% of claims.
Most prescribed
- Metoprolol Succinate436 claims
- Eliquis292 claims
- Atorvastatin Calcium257 claims
- Metoprolol Tartrate224 claims
- Furosemide208 claims
- Potassium Chloride156 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
- Medical Associates Clinic P CDubuque, IA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Thomas Mark Johnson among 169 cardiovascular disease physician records in Iowa
Thomas Mark Johnson, M.D. is one of 169 cardiovascular disease physician records with a practice address in Iowa. 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 2006, is newer than 27% of them.
- NPI issued2006 · 27% of these records are older, 40% newer
- In a Medicare fileYes · 83% of these records are
- In the CMS Doctors and Clinicians fileYes · 70% of these records are
- Graduated1974 · median 2000 among the 119 with a school on file
- Record last updated2009 · 63% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RC0000X and a Iowa practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Cardiovascular Disease Physician providers in Iowa
There are 169 cardiovascular disease physician records in Iowa.
All 169 in Iowa → Every provider in Dubuque → Cardiovascular Disease Physician nationwide →
The 8 cardiovascular disease physician records with the nearest ZIP codes
- Rami Eltibi, M.D.Dubuque, IA 520011932214194
- Tauseef Khan, M.D.Dubuque, IA 520011972585610
- Brian Loc, D.O.Dubuque, IA 520011033599691
- Charles Longo, M.D.Dubuque, IA 520011700855186
- Timothy Martin, M.D.Dubuque, IA 520011760441927
- Ramanujam Ramabadran, M.D.Dubuque, IA 520011417151143
- John Richardson, M.D.Dubuque, IA 520011235183872
- Nidal Harb, M.D.Coralville, IA 522411871572677
Common questions
What is Thomas Mark Johnson, M.D.'s NPI number?
Thomas Mark Johnson, M.D.'s National Provider Identifier (NPI) is 1801848486, issued on May 16, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Thomas Mark Johnson, M.D. located?
The NPPES record lists a practice address at 1000 Langworthy St, Dubuque, IA, 52001. Phone: (563) 584-3425. Providers update this record themselves, so call before visiting.
How can I verify Thomas Mark Johnson, M.D.'s license?
NPPES lists Iowa license number 21505, 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 Thomas Mark Johnson, M.D. prescribe under Medicare Part D?
In 2024, Thomas Mark Johnson, M.D. had 2,993 Medicare Part D claims for 438 beneficiaries; the average among cardiovascular disease physician prescribers was 3,078. 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.