Gregory Lorrain, MD
NPI 1033603550 · Anesthesiology Physician · Grand Rapids, MI
Enrolled with Medicare as Practitioner - Anesthesiology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Gregory Lorrain, MD is a Anesthesiology Physician provider in Grand Rapids, MI (NPI 1033603550).
Provider details
- NPI number
- 1033603550
- Entity type
- Individual
- Primary specialty
- Anesthesiology PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- 4301506834 (MI)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
8 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
34 Medicare services, 2024 (ranked within specialty)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Anesthesia for Other Procedure on Esophagus, Stomach, Or Upper Small Bowel Using an Endoscope00731 | 19 | $143 |
| Insertion of Artery Tube for Blood Sampling Or Infusion Through Skin36620 | 15 | $40 |
Typical Medicare-allowed amounts for these services range $40–$143 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, not a price quote and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
Practice location
Mailing address
Registry dates
- Enumerated
- 2018-06-18
- Last updated
- 2025-12-01
- Certified
- 2025-12-01
Frequently asked questions
- What is Gregory Lorrain's NPI number?
- Gregory Lorrain's National Provider Identifier (NPI) is 1033603550, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Gregory Lorrain's specialty?
- Gregory Lorrain is listed in the NPPES registry with a primary specialty of Anesthesiology Physician (Allopathic & Osteopathic Physicians).
- Where is Gregory Lorrain located?
- Gregory Lorrain's practice location on file with NPPES is 100 Michigan St Ne, Grand Rapids, MI 49503-2560.
- What is Gregory Lorrain's phone number?
- The practice phone number listed in the NPPES registry for Gregory Lorrain is (616) 391-1510.
- Does Gregory Lorrain accept Medicare?
- Gregory Lorrain is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Gregory Lorrain's NPI active?
- Yes — Gregory Lorrain's NPI (1033603550) is active in the NPPES registry as of the last update on 2025-12-01.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.