Doctor profile · Federal record

Dr. Rock Jean-Guillaume, D.O.

Emergency Medicine Physician (CMS: Emergency Medicine) · Holden, MA

  • NPI 1730157918
  • Accepts Medicare
  • 28 yrs in practice
  • Male
  • Group practice
  • No sanctions

Practice & contact

Operates at 3 locations .

NPPES Updated May 11, 2026
Primary practice
5 Shrewsbury St Ste D
Holden, MA 01520
(508) 829-3800
fax (508) 829-3802
Additional location
2040 Boston RD Ste 5
Wilbraham, MA 010951380
(413) 599-3800
fax (413) 279-1900
Additional location
55 Lake Ave N
Worcester, MA 016550002
(508) 421-1400
fax (508) 421-1490

Credentials & registration

NPPES · NUCC
NPI registered
March 2006 — 20 yrs on file
Profile last updated
November 22, 2020
Year of graduation
1998 — 28 yrs since
Specialty taxonomy
207P00000X — NUCC code
State license (1)
Massachusetts #215241
Medicaid
MA #110006102A

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1730157918. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
373
Distinct HCPCS
5
Medicare allowed
$50,090
HCPCS Description Services Patients Avg allowed
99285 Emergency department visit with high level of medical decision making 196 194 $168
99284 Emergency department visit with moderate level of medical decision making 119 118 $115
99283 Emergency department visit with low level of medical decision making 31 30 $68
90662 Influenza vaccine split virus, preservative free 14 14 $72
99211 Office or other outpatient visit for the evaluation and management of established patient that may not require presence of healthcare professional 13 12 $24

In context: peer comparison

Among 5 peers in this city , average services per provider: 55. This provider delivers 6.8× the peer median.

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
117
Patients
115
Total drug cost
$612
Drug Type Claims Patients Total cost
Prednisone Generic 37 35 $66
Cephalexin Generic 25 25 $153
Azithromycin Generic 20 20 $109
Ondansetron Odt (Ondansetron) Brand 20 20 $252
Oxycodone Hcl Generic 15 15 $32

Frequently asked questions

Auto-generated from federal data
What is Dr. Rock Jean-Guillaume's medical specialty?
Dr. Rock Jean-Guillaume practices Emergency Medicine Physician in Holden, MA.
Where does Dr. Rock Jean-Guillaume practice?
Dr. Rock Jean-Guillaume practices at 5 Shrewsbury St Ste D, Holden, MA 01520. Office phone: 5088293800.
What is Dr. Rock Jean-Guillaume's NPI?
Dr. Rock Jean-Guillaume's National Provider Identifier (NPI) is 1730157918, issued by NPPES.
Does Dr. Rock Jean-Guillaume accept Medicare assignment?
Yes. Dr. Rock Jean-Guillaume accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Rock Jean-Guillaume commonly perform?
Top Medicare-reported procedures in 2023: Emergency department visit with high level of medical decision making (HCPCS 99285); Emergency department visit with moderate level of medical decision making (HCPCS 99284); Emergency department visit with low level of medical decision making (HCPCS 99283). Source: CMS Medicare Physician & Other Practitioners file.