Howard Douglas Klein, M.D.
Internal Medicine Physician · Northampton, MA
Howard Douglas Klein, M.D. is an internal medicine physician with a practice address in Northampton, Massachusetts, and NPI 1063456325, issued on Jun 16, 2006. Check the license on the Massachusetts Board of Registration in Medicine; the Medicare figures below come from public CMS files.
- Name
- Howard Douglas Klein
- Credential
- M.D.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- 027988 CT
Self-reported in NPPES; status is on the state search - Practice location
- 421 N Main St, Northampton, MA 01060
- Phone
- (413) 584-4040
- Enumerated
- Jun 16, 2006
- Record last updated
- Jul 13, 2026
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 6,825 in Massachusetts → Look up another NPI →
Also registered at 421 N Main St
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Mary McDermott, M.S.W.Clinical Social Worker1972739456
- Corrina RileyPsychiatric/Mental Health Registered Nurse1073989299
- Daniel Schwartz, P.A.Physician Assistant1780620195
Verify Howard Douglas Klein in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMassachusetts Board of Registration in MedicineCheck the board
- 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
96% fewer Medicare Part D claims than the average internal medicine physician in 2024
120 Medicare Part D claims for 12 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D.
Most prescribed
- Lisinopril22 claims
- Metformin Hcl15 claims
- Atorvastatin Calcium14 claims
- Amlodipine Besylate12 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.
Howard Douglas Klein among 6,825 internal medicine physician records in Massachusetts
Howard Douglas Klein, M.D. is one of 6,825 internal medicine physician records with a practice address in Massachusetts. 75% 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 12% of them.
- NPI issued2006 · 12% of these records are older, 54% newer
- In a Medicare fileYes · 75% of these records are
- In the CMS Doctors and Clinicians fileNo · 60% of these records are
- Record last updated2026 · 64% 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 Massachusetts practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
21 internal medicine physician records list a practice address in Northampton
They are 21 of the 1,816 NPPES records with a practice address in Northampton, and 6,825 internal medicine physician records in Massachusetts.
All 6,825 in Massachusetts → Every provider in Northampton → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- David Alpern, MDNorthampton, MA 010601568422608
- Elizabeth Armstrong, M.D.Northampton, MA 010601881626786
- Edward Dean, MDNorthampton, MA 010601376528638
- Tara Dumont, MDNorthampton, MA 010601467515163
- Peter Elsea, MDNorthampton, MA 010601699731182
- Andrew Hall, M.D.Northampton, MA 010601073593679
- Anne McKinnon, MDNorthampton, MA 010601255311452
- James Most, MDNorthampton, MA 010601518982933
Common questions
What is Howard Douglas Klein, M.D.'s NPI number?
Howard Douglas Klein, M.D.'s National Provider Identifier (NPI) is 1063456325, issued on Jun 16, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Howard Douglas Klein, M.D. located?
The NPPES record lists a practice address at 421 N Main St, Northampton, MA, 01060. Phone: (413) 584-4040. Providers update this record themselves, so call before visiting.
How can I verify Howard Douglas Klein, M.D.'s license?
Search the Massachusetts Board of Registration in Medicine at https://findmydoctor.mass.gov/. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Howard Douglas Klein, M.D. prescribe under Medicare Part D?
In 2024, Howard Douglas Klein, M.D. had 120 Medicare Part D claims for 12 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.