Physician Profile
Gregory V Warren, MD
Unclaimed ProfileAbout Dr. Warren
Gregory V Warren, MD is a healthcare provider in Milwaukee, WI specializing in nephrology. According to Medicare claims data, Gregory cared for 206 Medicare patients across 376 services.
Summarised automatically from public NPI registry and CMS Medicare data. Not written or reviewed by this provider. Claim this profile to replace it.
Specialty
Credentials & Licensing
Source: NPPES NPI Registry
Contact Information
- (414) 672-8282
- Email not available
Practice Locations
3120 SOUTH 27TH STREET
Milwaukee, WI 53215
Procedures Most Often Billed to Medicare
376 services · 206 patients · 5 distinct codes
| Procedure | Type | Code | Services |
|---|---|---|---|
| Dialysis services, 4 or more physician visits per month (20 years or older) | Treatment | 90960 |
59 |
| Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes | Office visit | 99233 |
168 |
| Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more | Office visit | 99214 |
98 |
| Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes | Office visit | 99232 |
37 |
| Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes | Office visit | 99223 |
14 |
Source: CMS Medicare public data. Shows how often procedures were billed — not quality of care or patient satisfaction.
Related providers
Connections drawn from the registry and from what providers have told us. A link here is not a referral or an endorsement.
Other kidney specialists at this location 5
Same specialty, same street address — most likely the same department or group.
Also at this address 1
Providers at the same street address. Each files their own registry entry, so a shared practice often appears under several different names.
Other kidney specialists in Milwaukee 7
Same specialty, same city.
More connections — 5 related providers in 1 group
Also performs Dialysis services, 4 or more physician visits per month (20 years or older) 5
Providers in WI who bill this service to Medicare most often.
Common questions
What does Dr. Warren specialize in?
Dr. Warren is a kidney specialist in Milwaukee, WI. This is the primary taxonomy recorded against the NPI in the federal registry, listed there as “Nephrology”.
NPI registry
Where is Dr. Warren located?
Dr. Warren is listed at 3120 SOUTH 27TH STREET, Milwaukee, WI 53215. Addresses come from the NPI registry and can lag a move, so confirm before travelling.
NPI registry
What is Dr. Warren's phone number?
The number on file is (414) 672-8282. Guide.md cannot book appointments or pass on messages — please call the office directly.
NPI registry
What is Dr. Warren's NPI number?
Dr. Warren's National Provider Identifier is 1649262544. It is issued by the Centers for Medicare & Medicaid Services and is unique and permanent — it does not change if they move practice.
NPI registry
How long has Dr. Warren been practicing?
Dr. Warren has 21+ years experience. Registered with an NPI since 2005. National Provider Identifiers only began in 2005, so a provider who qualified earlier may have practiced for longer than this.
NPI registry
What does Dr. Warren do most often?
According to Medicare billing data, Dr. Warren provides treatments such as dialysis services, 4 or more physician visits per month, alongside routine visits and testing. This reflects Medicare patients only and is billing volume, not a measure of quality.
Medicare claims
Has Dr. Warren confirmed this information?
Not yet. This profile is built from public federal data and has not been confirmed by Dr. Warren. If this is you, claiming it is free.
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Claim this profileProvider data sourced from the NPPES NPI Registry and CMS public datasets. Information is provided for reference and is not medical advice.