Gregorio J Guillen, MD - Medicare Internal Medicine in Perth Amboy, NJ

Gregorio J Guillen, MD is a medicare enrolled "Internal Medicine - Geriatric Medicine" physician in Perth Amboy, New Jersey. He graduated from medical school in 1982 and has 42 years of diverse experience with area of expertise as Internal Medicine. His current practice location is 400 State St. Suite 2, Perth Amboy, New Jersey. You can reach out to his office (for appointments etc.) via phone at (732) 442-6020.

Gregorio J Guillen is licensed to practice in New Jersey (license number MA56159) and he also participates in the medicare program. He accepts medicare assignments (which means he accepts the Medicare-approved amount; you will not be billed for any more than the Medicare deductible and coinsurance) and his NPI Number is 1538252226.

Contact Information

Gregorio J Guillen, MD
400 State St. Suite 2,
Perth Amboy, NJ 08861
(732) 442-6020
(732) 442-1995

Map and Direction




Physician's Profile

Full NameGregorio J Guillen
GenderMale
SpecialityInternal Medicine
Experience42 Years
Location400 State St. Suite 2, Perth Amboy, New Jersey
Accepts Medicare AssignmentsYes. He accepts the Medicare-approved amount; you will not be billed for any more than the Medicare deductible and coinsurance.
  Medical Education and Training:
  • Gregorio J Guillen graduated from medical school in 1982
  NPI Data:
  • NPI Number: 1538252226
  • Provider Enumeration Date: 10/02/2006
  • Last Update Date: 08/06/2013
  Medicare PECOS Information:
  • PECOS PAC ID: 5991756926
  • Enrollment ID: I20050207000626

Medical Identifiers

Medical identifiers for Gregorio J Guillen such as npi, medicare ID, medicare PIN, medicaid, etc.
IdentifierTypeStateIssuer
1538252226NPI-NPPES
6523706MedicaidNJ

Medical Taxonomies and Licenses

TaxonomyTypeLicense (State)Status
207RG0300XInternal Medicine - Geriatric Medicine MA56159 (New Jersey)Primary

Medical Facilities Affiliation

Facility NameLocationFacility Type
Raritan Bay Medical Center Perth Amboy DivisionPerth amboy, NJHospital
Alameda Center For Rehabilitation And HealthcarePerth amboy, NJNursing home

Medicare Reassignments

Some practitioners may not bill the customers directly but medicare billing happens through clinics / group practice / hospitals where the provider works. Medicare reassignment of benefits is a mechanism by which practitioners allow third parties to bill and receive payment for medicare services performed by them. Gregorio J Guillen allows following entities to bill medicare on his behalf.
Entity NameGregorio J. Guillen Md, Pc
Entity TypePart B Supplier - Clinic/group Practice
Entity IdentifiersNPI Number: 1518052950
PECOS PAC ID: 0446202006
Enrollment ID: O20050211000667

Medicare Part D Prescriber Enrollment

Any physician or other eligible professional who prescribes Part D drugs must either enroll in the Medicare program or opt out in order to prescribe drugs to their patients with Part D prescription drug benefit plans. Gregorio J Guillen is enrolled with medicare and thus, if eligible, can prescribe medicare part D drugs to patients with medicare part D benefits.

Mailing Address and Practice Location

Mailing AddressPractice Location Address
Gregorio J Guillen, MD
Po Box 1608,
Perth Amboy, NJ 08862-1608

Ph: (732) 442-6020
Gregorio J Guillen, MD
400 State St. Suite 2,
Perth Amboy, NJ 08861

Ph: (732) 442-6020

Reviews and Comments


Internal Medicine Doctors in Perth Amboy, NJ

Pankaj R Shirolawala, M.D.
Geriatric Medicine
Medicare: Accepting Medicare Assignments
Practice Location: 609 Amboy Ave Ste 101, Perth Amboy, NJ 08861
Phone: 732-442-2211    Fax: 732-326-0517
Dr. Mahesh H Bhagat, MD
Geriatric Medicine
Medicare: Medicare Enrolled
Practice Location: 530 New Brunswick Ave, Perth Amboy, NJ 08861
Phone: 732-442-3700    
Dr. Mohammed Islam, MD
Geriatric Medicine
Medicare: Accepting Medicare Assignments
Practice Location: Rbmc 530 New Brunswick Ave, Dept Of Internal Medicine, Perth Amboy, NJ 08861
Phone: 732-324-5080    Fax: 732-324-4669
Poonam Pamini Jani, M.D.
Geriatric Medicine
Medicare: Accepting Medicare Assignments
Practice Location: 275 Hobart St, Perth Amboy, NJ 08861
Phone: 732-376-9333    Fax: 732-293-0139
Dr. Alissa Kay Holman, M.D.
Geriatric Medicine
Medicare: Accepting Medicare Assignments
Practice Location: 530 New Brunswick Ave, Perth Amboy, NJ 08861
Phone: 732-442-3700    
Sana Ahsun, MD
Geriatric Medicine
Medicare: Medicare Enrolled
Practice Location: 275 Hobart St, Perth Amboy, NJ 08861
Phone: 732-376-9333    
Cynthia Vuittonet, M.D.
Geriatric Medicine
Medicare: Accepting Medicare Assignments
Practice Location: 275 Hobart St, Perth Amboy, NJ 08861
Phone: 732-376-9333    

Medicare Program: Medicare is a federal government program which provides health insurance to people who are 65 or older. This program also covers certain younger people with disabilities (who receive Social Security Disability Insurance - SSDI), and people with End-Stage Renal Disease (permanent kidney failure requiring dialysis or a transplant, sometimes called ESRD.

Medicare Assignment: Assignment means that your doctor, provider, or supplier agrees (or is required by law) to accept the Medicare-approved amount as full payment for covered services. Most doctors, providers, and suppliers accept assignment, but you should always check to make sure. Participating providers have signed an agreement to accept assignment for all Medicare-covered services.

NPI Number: The National Provider Identifier (NPI) is a unique identification number for covered health care providers. The NPI must be used in lieu of legacy provider identifiers in the HIPAA standards transactions. Covered health care providers and all health plans and health care clearinghouses must use the NPIs in the administrative and financial transactions adopted under HIPAA (Health Insurance Portability and Accountability Act).

Our Data: Information on www.medicarelist.com is built using data sources published by Centers for Medicare & Medicaid Services (CMS) under Freedom of Information Act (FOIA). The information disclosed on the NPI Registry are FOIA-disclosable and are required to be disclosed under the FOIA and the eFOIA amendments to the FOIA. There is no way to 'opt out' or 'suppress' the NPPES record data for health care providers with active NPIs.