Doctor profile · Federal record

Dr. Gregorio Guillen, M.D

Geriatric Medicine (Internal Medicine) Physician (CMS: Internal Medicine) · Perth Amboy, NJ

  • NPI 1538252226
  • Accepts Medicare
  • 44 yrs in practice
  • Male
  • Solo practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
400 State St. Suite 2
Perth Amboy, NJ 08861
(732) 442-6020
fax (732) 442-1995
Mailing address
Po Box 1608
Perth Amboy, NJ 088621608

Credentials & registration

NPPES · NUCC
NPI registered
October 2006 — 20 yrs on file
Profile last updated
August 6, 2013
Year of graduation
1982 — 44 yrs since
Specialty taxonomy
207RG0300X — NUCC code
State license (1)
New Jersey #MA56159
Medicaid
NJ #6523706

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1538252226. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
1,294
Distinct HCPCS
10
Medicare allowed
$127,830
HCPCS Description Services Patients Avg allowed
99214 Established patient office or other outpatient visit, 30-39 minutes 404 171 $141
99213 Established patient office or other outpatient visit, 20-29 minutes 223 130 $98
99497 Advance care planning, first 30 minutes 133 133 $90
G0439 Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit 105 105 $142
G0444 Annual depression screening, 5 to 15 minutes 104 104 $21
G0008 Administration of influenza virus vaccine 65 64 $34
93000 Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report 53 49 $16
90694 Influenza vaccine, quadrivalent inactivated, 0.5 ml dosage 51 51 $76
99212 Established patient office or other outpatient visit, 10-19 minutes 43 37 $63
77080 Dxa bone density measurement of hip, pelvis, spine 31 31 $44

In context: peer comparison

Among 1 peers in this city , average services per provider: 86. This provider delivers 15× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$1,761
Transactions
101
Manufacturers
15
Payer (manufacturer) Industry Txns Amount
AstraZeneca Pharmaceuticals LP 12 $247.40
Bayer Healthcare Pharmaceuticals Inc. 12 $243.00
Novartis Pharmaceuticals Corporation 13 $229.23
ABBVIE INC. 11 $157.77
GlaxoSmithKline, LLC. 10 $150.94
Amgen Inc. 10 $146.57
Boehringer Ingelheim Pharmaceuticals, Inc. 7 $100.86
Exact Sciences Corporation 4 $79.99
Novo Nordisk Inc 5 $78.95
Lilly USA, LLC 5 $75.43
Corcept Therapeutics 4 $56.74
IRONWOOD PHARMACEUTICALS, INC 2 $37.53
Lundbeck LLC 2 $33.69
Mylan Specialty L.P. 2 $33.02
Eisai Inc. 2 $27.22

By nature of payment

Food and Beverage
$1,753
Education
$8

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
5,240
Patients
1,501
Total drug cost
$254,138
Drug Type Claims Patients Total cost
Atorvastatin Calcium Generic 809 258 $15,262
Omeprazole Generic 552 147 $7,641
Amlodipine Besylate Generic 503 158 $4,869
Metoprolol Succinate Generic 410 111 $12,509
Pantoprazole Sodium Generic 363 98 $4,749
Albuterol Sulfate Hfa (Albuterol Sulfate) Brand 330 74 $12,643
Losartan Potassium Generic 306 93 $4,655
Metformin Hcl Generic 285 89 $2,987
Gabapentin Generic 273 77 $3,970
Donepezil Hcl Generic 254 79 $5,332

Frequently asked questions

Auto-generated from federal data
What is Dr. Gregorio Guillen's medical specialty?
Dr. Gregorio Guillen practices Geriatric Medicine (Internal Medicine) Physician in Perth Amboy, NJ.
Where does Dr. Gregorio Guillen practice?
Dr. Gregorio Guillen practices at 400 State St. Suite 2, Perth Amboy, NJ 08861. Office phone: 7324426020.
What is Dr. Gregorio Guillen's NPI?
Dr. Gregorio Guillen's National Provider Identifier (NPI) is 1538252226, issued by NPPES.
Does Dr. Gregorio Guillen accept Medicare assignment?
Yes. Dr. Gregorio Guillen accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Gregorio Guillen commonly perform?
Top Medicare-reported procedures in 2023: Established patient office or other outpatient visit (HCPCS 99214); Established patient office or other outpatient visit (HCPCS 99213); Advance care planning (HCPCS 99497). Source: CMS Medicare Physician & Other Practitioners file.