Dr. John Massaro, DO
- Part D claims, 2024
- 154
- Hospital affiliations
- 1
- Medical group
- 1
- Insurance carriers
- 4
- State license
- 1
- Practice address
- 1911 Johnson Ave, San Luis Obispo, CA 93401
- Practice phone
- Call (805) 543-5353
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Find Dr. Massaro's professional email, personal email and mobile number
Dmand AI checks each channel through healthcare-specific waterfall enrichment. See what is on file with a free account, with practice phones, licenses and affiliations.
Dr. John Massaro is an internist in San Luis Obispo, California
Dr. Massaro practices at Dignity Health - French Hospital Medical Center in San Luis Obispo, California, part of CommonSpirit Health.
Dr. Massaro's NPI, 1588665293, was assigned on August 3, 2005. Dr. Massaro graduated from New York Institute of Technology College of Osteopathic Medicine - Old Westbury in 1997. Dr. Massaro holds California license 20A7971.
- NPI
- 1588665293NPI Registry (opens in a new tab)
- NPI enumeration date
- August 3, 2005
- NPI status
- Active
- Practice phone
- (805) 543-5353
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Male
- Medical school graduation
- 1997
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Affiliation Data
Dr. John Massaro practices at Dignity Health - French Hospital Medical Center in San Luis Obispo, California
Dr. Massaro's primary practice is Dignity Health - French Hospital Medical Center, at 1911 Johnson Ave, San Luis Obispo, CA 93401 in San Luis Obispo County. The practice phone is (805) 543-5353.
- Dignity Health - French Hospital Medical Center1911 Johnson Ave, San Luis Obispo, CA 93401 · San Luis Obispo CountyPhone(805) 543-5353
Source: Dmand AI Affiliation Data
Dr. John Massaro is affiliated with 2 sites of care and 1 medical group
Dr. Massaro's primary practice is Dignity Health - French Hospital Medical Center in San Luis Obispo, California, part of CommonSpirit Health. The medical group on file is Bakersfield Family Medical Center. Dmand AI also links Dr. Massaro to 1 more group practice or clinic, named with a free account.
Sources: Dmand AI Affiliation Data; and Dmand AI Org Hierarchy Data
Dmand AI tracks the EHR system at Dr. John Massaro's practice
Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Massaro practices, 2 sites in all. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| Dignity Health - French Hospital Medical Center | Available with a free account |
| +1 more affiliated site | Available with a free account |
Source: Dmand AI Technology Install Data
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Dr. John Massaro is one of 16,751 internists in California
Internal medicine is Dr. Massaro's primary specialty in the NPI Registry, under taxonomy code 207R00000X. Dr. Massaro is board certified in internal medicine by the American Board of Internal Medicine. Dr. Massaro is licensed in California.
Specialties and state licenses
- Internal medicine, CaliforniaPrimary
Internists near Dr. Massaro
Counts of internists with a Dmand AI profile, by place and practice. Each opens the list.
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Peer Benchmarks
Dr. John Massaro's patients have a median age of 77
Across all payers, Dmand AI patient panel data puts Dr. Massaro's median patient age at 77, with 56% women.
Dr. Massaro's patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 77
Patient panel by sex, all payers
- Women56%
- Men43%
Source: Dmand AI Patient Panel Data
Dr. John Massaro wrote 154 Medicare Part D claims in 2024
In 2024, Dr. Massaro wrote 154 Medicare Part D claims for 57 patients. 85% of them were for generic drugs. CMS names the drug for 11 of them, across 1 drug with 11 or more claims each, at $7,437 in total drug cost. In 2023, CMS named 100 claims across 7 drugs.
Dr. Massaro's Part D claims by kind of drug, 2024
- Generic131 claims85%
- Brand-name and other23 claims15%
Dr. Massaro's most prescribed drugs by claims, 2024
CMS names a drug when it has 11 or more claims. Share is of the claims for drugs CMS names.
Drug classes CMS tracks in Dr. Massaro's Part D claims, 2024
- Antibiotics16%25 of 154 claims
Share of all Part D claims for each drug class CMS reports on. Classes with no claims are left out.
Part D claims for drugs CMS names, 2023 to 2024
- 2023
- 2024
- Claims for drugs CMS names
- 2023: 1002024: 1189%
Drugs named by CMS: 1 in 2024, 7 in 2023.
Sources: Medicare Part D Prescribers - by Provider and Drug (CMS), 2024 data, released May 6, 2026; and Medicare Part D Prescribers - by Provider (CMS), 2024 data
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Dr. John Massaro graduated from New York Institute of Technology College of Osteopathic Medicine - Old Westbury
Dr. Massaro graduated from New York Institute of Technology College of Osteopathic Medicine - Old Westbury in 1997.
- Medical school
- Board certified in internal medicine
- Board certified in 2001 - 2027
- Board certified in 2000 - 2004
- Board certified in 2000 - 2004
- Board certified in 2001 - 2002
Source: Dmand AI Professional Profile Data
Dr. John Massaro accepts plans from 4 insurance carriers
Dr. Massaro is in network with 4 carriers, including Blue Cross Blue Shield of Massachusetts, Blue Cross Blue Shield of Michigan and HCSC. PPO plans come from the most carriers, 4. Check the plan with the practice before a visit.
- Blue Cross Blue Shield of Massachusetts
- Blue Cross Blue Shield of Michigan
- HCSC
- Elevance
Plan types Dr. Massaro accepts, by number of carriers
- PPO4
- Medicare3
Source: Dmand AI Insurance Network Data
Sources for Dr. John Massaro's profile data
| Data on this page | Source |
|---|---|
| NPI, name, sex, specialty and licenses | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Professional Profile Data |
| Practice locations and phone | Dmand AI Affiliation Data |
| Primary practice, affiliations and health system | Dmand AI Affiliation DataDmand AI Org Hierarchy Data |
| Medicare patients and the all-payer patient panel | Dmand AI Patient Panel Data |
| Part D prescribing | Medicare Part D Prescribers - by Provider and Drug (CMS) (opens in a new tab)Medicare Part D Prescribers - by Provider (CMS) (opens in a new tab) |
| Training, board certification and memberships | Dmand AI Professional Profile Data |
| Insurance carriers and plan types | Dmand AI Insurance Network Data |
| EHR at each practice site | Dmand AI Technology Install Data |
| Similar physicians | Dmand AI Affiliation Data |
Data last refreshed October 2026Report an inaccuracyRemove my information
FAQ
Frequently asked questions about Dr. John Massaro
Spotted something out of date? Email hello@dmand.ai and we will check the record. Contact details live in the free trial.
What is Dr. John Massaro's NPI number?
Dr. John Massaro's NPI number is 1588665293. It was assigned on August 3, 2005, and it is active in the NPI Registry.
What kind of doctor is Dr. John Massaro?
Dr. John Massaro is an internist in San Luis Obispo, California. The primary specialty in the NPI Registry is Internal Medicine Physician (taxonomy code 207R00000X).
Where does Dr. John Massaro practice?
Dr. Massaro practices at 1911 Johnson Ave, San Luis Obispo, CA 93401. Dr. Massaro's primary practice is Dignity Health - French Hospital Medical Center in San Luis Obispo, California, part of CommonSpirit Health. Dmand AI also links Dr. Massaro to 1 group practice or clinic.
What is Dr. John Massaro's office phone number?
The practice phone on file for Dr. Massaro is (805) 543-5353.
What is Dr. John Massaro's medical license number?
Dr. Massaro holds California license 20A7971.
Which hospitals is Dr. John Massaro affiliated with?
Dr. Massaro practices at Dignity Health - French Hospital Medical Center in San Luis Obispo, California.
What medical group is Dr. John Massaro part of?
Dr. Massaro is linked to Bakersfield Family Medical Center.
Is Dr. John Massaro board certified?
Yes. Dr. Massaro is board certified in internal medicine by the American Board of Internal Medicine.
Where did Dr. John Massaro go to medical school?
Dr. Massaro graduated from New York Institute of Technology College of Osteopathic Medicine - Old Westbury in 1997.
What drugs does Dr. John Massaro prescribe most?
In 2024 Medicare Part D data, Dr. Massaro's most prescribed drugs by claims were Eliquis.
How long has Dr. John Massaro been practicing?
Dr. Massaro graduated from medical school in 1997, 29 years ago.
What insurance does Dr. John Massaro accept?
Dr. Massaro is in network with 4 carriers, including Blue Cross Blue Shield of Massachusetts, Blue Cross Blue Shield of Michigan and HCSC. PPO plans come from the most carriers, 4. Check the plan with the practice before a visit.
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