Dr. Michael Nmn Grassia, MD
- Medicare services, 2024
- 1,739
- Medicare patients, 2024
- 512
- Part D claims, 2024
- 631
- Hospital affiliations
- 5
- Industry payments
- $1,959
- Practice address
- 6160 Kempsville Cir, Norfolk, VA 23502
- Practice phone
- Call (757) 466-9288
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Primary practice
Nephrology Associates of Tidewater Ltd
Norfolk, Virginia
Find Dr. Grassia'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. Michael Nmn Grassia is a nephrologist in Norfolk, Virginia
Dr. Grassia practices at Nephrology Associates of Tidewater Ltd in Norfolk, Virginia.
Dr. Grassia's NPI, 1235128133, was assigned on October 14, 2005. Dr. Grassia graduated from Macon & Joan Brock Virginia Health Sciences Eastern Virginia Medical School in 1997. Dr. Grassia holds Virginia license 0101232951.
- NPI
- 1235128133NPI Registry (opens in a new tab)
- Medicare PAC ID
- 2961458062
- NPI enumeration date
- October 14, 2005
- NPI status
- Active
- Accepts Medicare assignment
- Yes
- Practice phone
- (757) 466-9288
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Male
- Estimated age
- 55
- Medical school graduation
- 1997
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; Dmand AI Practice Data; and Doctors and Clinicians National Downloadable File (CMS)
Dr. Michael Nmn Grassia practices at Nephrology Associates of Tidewater Ltd in Norfolk, Virginia
Dr. Grassia's primary practice is Nephrology Associates of Tidewater Ltd, at 6160 Kempsville Cir, Norfolk, VA 23502 in Norfolk City. The practice phone is (757) 466-9288.
- Nephrology Associates of Tidewater Ltd6160 Kempsville Cir, Norfolk, VA 23502 · Norfolk CityPhone(757) 466-9288
Sources: NPPES NPI Registry (CMS); and Dmand AI Practice Data
Dr. Michael Nmn Grassia is affiliated with 8 sites of care and 1 medical group
Dr. Grassia's primary practice is Nephrology Associates of Tidewater Ltd in Norfolk, Virginia. Dr. Grassia is also affiliated with Sentara Leigh Hospital. The medical group on file is Nephrology Associates of Tidewater, LTD. Dmand AI also links Dr. Grassia to 4 more hospitals, 1 dialysis center and 1 group practice or clinic, each named with a free account.
Sources: NPPES NPI Registry (CMS); Dmand AI Practice Data; and Dmand AI Affiliation Data
Dmand AI tracks the EHR system at Dr. Michael Nmn Grassia's practice
Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Grassia practices, 7 sites in all. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| Nephrology Associates of Tidewater Ltd | Available with a free account |
| +7 more affiliated sites | Available with a free account |
Source: Dmand AI Technology Install Data
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Dr. Michael Nmn Grassia is one of 289 nephrologists in Virginia
Nephrology is Dr. Grassia's primary specialty in the NPI Registry, under taxonomy code 207RN0300X. Dr. Grassia is board certified in nephrology by the American Board of Internal Medicine. Dmand AI has Dr. Grassia's licenses on file in 2 states: Virginia and Pennsylvania.
Specialties and state licenses
- Nephrology, VirginiaPrimary
- Pennsylvania license
Clinical focus
Dmand AI lists acute kidney failure, chronic kidney disease, fluid and electrolyte imbalances and kidney cysts among the conditions Dr. Grassia treats.
Nephrologists near Dr. Grassia
Counts of nephrologists 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. Michael Nmn Grassia billed Medicare for 1,739 services in 2024
CMS data shows 1,739 Medicare services from Dr. Grassia across 10 procedure codes in 2024, for 512 Medicare patients. Medicare paid $162,309 for them.
Dr. Grassia's Medicare services by type, 2023 to 2024
- 2023
- 2024
- Office and hospital visits
- 2023: 8952024: 1,14828%
- Tests and treatments
- 2023: 3782024: 3673%
- Other services
- 2023: 02024: 224
Where Dr. Grassia's Medicare services took place, 2024
- In an office98156%
- In a facility75844%
Dr. Grassia compared with the Virginia median for nephrologists, 2024
- Dr. Grassia
- Virginia median
- Medicare services
- 1,739vs 1,22742% above
- Medicare patients
- 512vs 38732% above
- Part D claims
- 480vs 77038% below
Medians across 276 nephrologists in Virginia with Dmand AI profiles that report each measure.
Dr. Grassia's most billed Medicare procedure codes, 2024
CMS publishes codes billed for 11 or more Medicare patients. Each label is the code family; CPT descriptions are licensed by the AMA.
Need commercial claims for Dr. Grassia?
Medicare shows one payer. Book a meeting to get commercial claims data for Dr. Grassia and other nephrologists in Virginia.
Sources: Medicare Physician & Other Practitioners - by Provider and Service (CMS), 2024 data; and Dmand AI Peer Benchmarks
Dr. Michael Nmn Grassia treated 512 Medicare patients in 2024, average age 74
CMS counts 512 Medicare patients who saw Dr. Grassia in 2024. The largest group is 75 to 84, with 209 patients. 75% of them have chronic kidney disease, and 75% have high blood pressure. 16% are also on Medicaid. Their average risk score is 3.82, where 1.00 is the Medicare average, so they are sicker than most Medicare patients.
Across all payers, Dmand AI patient panel data puts Dr. Grassia's median patient age at 72, with 55% women.
Dr. Grassia's Medicare patients by age, 2024
Dr. Grassia's Medicare patients by sex, 2024
- Women26752%
- Men24548%
Chronic conditions among Dr. Grassia's Medicare patients, 2024
- Chronic kidney disease75%
- High blood pressure75%
- High cholesterol75%
- Diabetes61%
- Heart failure54%
- Ischemic heart disease48%
- Arthritis46%
- Atrial fibrillation36%
Share of Medicare patients with each condition. A patient can have several.
Dr. Grassia's patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 72
Patient panel by sex, all payers
- Women55%
- Men44%
Sources: Dmand AI Patient Panel Data; and Medicare Physician & Other Practitioners - by Provider (CMS), 2024 data
Dr. Michael Nmn Grassia wrote 631 Medicare Part D claims in 2024
In 2024, Dr. Grassia wrote 631 Medicare Part D claims for 113 patients. 87% of them were for generic drugs. CMS names the drug for 480 of them, across 17 drugs with 11 or more claims each, at $44,632 in total drug cost. In 2023, CMS named 455 claims across 18 drugs.
Dr. Grassia's Part D claims by kind of drug, 2024
- Generic552 claims87%
- Brand-name79 claims13%
Dr. Grassia'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. Grassia's Part D claims, 2024
- Antibiotics2%13 of 631 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: 4552024: 4805%
Drugs named by CMS: 17 in 2024, 18 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
How Dr. Michael Nmn Grassia takes part in Medicare
Dr. Grassia accepts Medicare assignment, so Medicare's approved amount is taken as full payment.
- Accepts Medicare assignment
- Yes
Source: Doctors and Clinicians National Downloadable File (CMS)
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Dr. Michael Nmn Grassia received $1,959 in industry payments from 2016 to 2025
CMS Open Payments shows 94 general payments to Dr. Grassia from 16 drug and device companies from 2016 to 2025. Food and beverage make up the largest share, 89% of the total. Otsuka America Pharmaceutical, Inc. paid the most, $409.
General payments to Dr. Grassia by program year, 2016 to 2025
General payments to Dr. Grassia by kind, 2016 to 2025
- Food and beverage$1,74489%
- Education$21511%
Companies that paid Dr. Grassia the most, 2016 to 2025
Share is of all general payments to this clinician.
Source: Open Payments (CMS), 2025 data, released July 7, 2026
Dr. Michael Nmn Grassia has 1 award and honors on record
Dmand AI lists 1 award for Dr. Grassia, most recently CMS Stage 1 EHR in 2012.
Awards and honors for Dr. Grassia
- 2012
- CMS Stage 1 EHR
Source: Dmand AI Professional Profile Data
Dr. Michael Nmn Grassia graduated from Macon & Joan Brock Virginia Health Sciences Eastern Virginia Medical School
Dr. Grassia graduated from Macon & Joan Brock Virginia Health Sciences Eastern Virginia Medical School in 1997.
- Medical school
- Board certified in nephrology
Source: Dmand AI Professional Profile Data
Dr. Michael Nmn Grassia accepts plans from 18 insurance carriers
Dr. Grassia is in network with 18 carriers, including Aetna, United Healthcare and Elevance. PPO plans come from the most carriers, 11. Check the plan with the practice before a visit.
- Aetna
- United Healthcare
- Elevance
- HCSC
- Molina
- Aspirus Health Plan
- Blue Cross Blue Shield of Massachusetts
- Blue Cross Blue Shield of Michigan
- +10 more carriersWith a free account
Plan types Dr. Grassia accepts, by number of carriers
- PPO11
- HMO8
- Medicare8
- EPO5
- POS3
- Medicaid2
Source: Dmand AI Insurance Network Data
Sources for Dr. Michael Nmn Grassia'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 | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Practice Data |
| Primary practice, affiliations and health system | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Practice DataDmand AI Affiliation Data |
| Medicare services and procedure codes | Medicare Physician & Other Practitioners - by Provider and Service (CMS) (opens in a new tab) |
| State medians for the same specialty | Dmand AI Peer Benchmarks |
| Medicare patients and the all-payer patient panel | Dmand AI Patient Panel DataMedicare Physician & Other Practitioners - by Provider (CMS) (opens in a new tab) |
| 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) |
| MIPS scores, telehealth, assignment and procedure percentiles | Doctors and Clinicians National Downloadable File (CMS) (opens in a new tab) |
| Industry payments | Open Payments (CMS) (opens in a new tab) |
| Awards and committee roles | Dmand AI Professional Profile Data |
| 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. Michael Nmn Grassia
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. Michael Nmn Grassia's NPI number?
Dr. Michael Nmn Grassia's NPI number is 1235128133. It was assigned on October 14, 2005, and it is active in the NPI Registry.
What kind of doctor is Dr. Michael Nmn Grassia?
Dr. Michael Nmn Grassia is a nephrologist in Norfolk, Virginia. The primary specialty in the NPI Registry is Nephrology Physician (taxonomy code 207RN0300X).
Where does Dr. Michael Nmn Grassia practice?
Dr. Grassia practices at 6160 Kempsville Cir, Norfolk, VA 23502. Dr. Grassia's primary practice is Nephrology Associates of Tidewater Ltd in Norfolk, Virginia. Dmand AI also links Dr. Grassia to 4 hospitals, 1 dialysis center and 1 group practice or clinic.
What is Dr. Michael Nmn Grassia's office phone number?
The practice phone on file for Dr. Grassia is (757) 466-9288.
What is Dr. Michael Nmn Grassia's medical license number?
Dr. Grassia holds Virginia license 0101232951, one of the licenses on file in 2 states.
Which states has Dr. Michael Nmn Grassia been licensed in?
Dmand AI has state licenses on file for Dr. Grassia in Virginia (2000 to 2026) and Pennsylvania (1998 to 2002).
Which hospitals is Dr. Michael Nmn Grassia affiliated with?
Dr. Grassia is affiliated with Sentara Leigh Hospital. Dmand AI links Dr. Grassia to 4 more hospitals.
What medical group is Dr. Michael Nmn Grassia part of?
Dr. Grassia is linked to Nephrology Associates of Tidewater, LTD.
Does Dr. Michael Nmn Grassia accept Medicare?
Yes. CMS data shows Dr. Grassia billed Medicare for 1,739 services in 2024, and Dr. Grassia accepts Medicare assignment.
How many Medicare patients does Dr. Michael Nmn Grassia see?
CMS counts 512 Medicare patients who saw Dr. Grassia in 2024, with an average age of 74.
Show 7 more questionsShow fewer questions
Is Dr. Michael Nmn Grassia board certified?
Yes. Dr. Grassia is board certified in nephrology by the American Board of Internal Medicine.
What services does Dr. Michael Nmn Grassia bill to Medicare?
In 2024, Dr. Grassia's most billed Medicare services were hospital inpatient care (99232), dialysis (90960) and medicare service (G2211).
Where did Dr. Michael Nmn Grassia go to medical school?
Dr. Grassia graduated from Macon & Joan Brock Virginia Health Sciences Eastern Virginia Medical School in 1997.
What drugs does Dr. Michael Nmn Grassia prescribe most?
In 2024 Medicare Part D data, Dr. Grassia's most prescribed drugs by claims were Losartan Potassium, Lisinopril and Furosemide.
Has Dr. Michael Nmn Grassia received payments from drug or device companies?
CMS Open Payments shows $1,959 in general payments to Dr. Grassia from 16 companies from 2016 to 2025. The largest total came from Otsuka America Pharmaceutical, Inc.
How long has Dr. Michael Nmn Grassia been practicing?
Dr. Grassia graduated from medical school in 1997, 29 years ago.
What insurance does Dr. Michael Nmn Grassia accept?
Dr. Grassia is in network with 18 carriers, including Aetna, United Healthcare and Elevance. PPO plans come from the most carriers, 11. Check the plan with the practice before a visit.
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