Geraldine A Ryan, MD - Medicare Family Practice in O Fallon, MO

Geraldine A Ryan, MD is a medicare enrolled "Internal Medicine" physician in O Fallon, Missouri. She went to Saint Louis University School Of Medicine and graduated in 1988 and has 36 years of diverse experience with area of expertise as Family Practice. She is a member of the group practice Mercy Clinic East Communities and her current practice location is 9426 Phoenix Village Pkwy, O Fallon, Missouri. You can reach out to her office (for appointments etc.) via phone at (636) 561-5999.

Geraldine A Ryan is licensed to practice in Missouri (license number 100756) and she also participates in the medicare program. She accepts medicare assignments (which means she accepts the Medicare-approved amount; you will not be billed for any more than the Medicare deductible and coinsurance) and her NPI Number is 1689640609.

Contact Information

Geraldine A Ryan, MD
9426 Phoenix Village Pkwy,
O Fallon, MO 63368-4781
(636) 561-5999
(636) 561-4746

Map and Direction




Physician's Profile

Full NameGeraldine A Ryan
GenderFemale
SpecialityFamily Practice
Experience36 Years
Location9426 Phoenix Village Pkwy, O Fallon, Missouri
Accepts Medicare AssignmentsYes. She accepts the Medicare-approved amount; you will not be billed for any more than the Medicare deductible and coinsurance.
  Medical Education and Training:
  • Geraldine A Ryan attended and graduated from Saint Louis University School Of Medicine in 1988
  NPI Data:
  • NPI Number: 1689640609
  • Provider Enumeration Date: 02/28/2006
  • Last Update Date: 04/02/2015
  Medicare PECOS Information:
  • PECOS PAC ID: 7810094828
  • Enrollment ID: I20070525000044

Medical Identifiers

Medical identifiers for Geraldine A Ryan such as npi, medicare ID, medicare PIN, medicaid, etc.
IdentifierTypeStateIssuer
1689640609NPI-NPPES
110211326OtherMORAILROAD MEDICARE

Medical Taxonomies and Licenses

TaxonomyTypeLicense (State)Status
207R00000XInternal Medicine 100756 (Missouri)Primary
208000000XPediatrics 100756 (Missouri)Secondary

Medical Facilities Affiliation

Facility NameLocationFacility Type
Mercy Hospital St LouisSaint louis, MOHospital
St Lukes HospitalChesterfield, MOHospital

Group Practice Association

Group Practice NameGroup PECOS PAC IDNo. of Members
Mercy Clinic East Communities7214827922499

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. Geraldine A Ryan allows following entities to bill medicare on her behalf.
Entity NameMercy Clinic East Communities
Entity TypePart B Supplier - Clinic/group Practice
Entity IdentifiersNPI Number: 1851335228
PECOS PAC ID: 7214827922
Enrollment ID: O20070521000006

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. Geraldine A Ryan 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
Geraldine A Ryan, MD
9426 Phoenix Village Pkwy,
O Fallon, MO 63368-4781

Ph: (636) 561-5999
Geraldine A Ryan, MD
9426 Phoenix Village Pkwy,
O Fallon, MO 63368-4781

Ph: (636) 561-5999

Reviews and Comments


Internal Medicine Doctors in O Fallon, MO

Brian A Grus, MD
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Dr. Amy Kathleen Davis, M.D.
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Dr. Saadia Taufiq Raza, MD
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Dr. Genevieve Catherine Matthews, MD
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Practice Location: 20 Progress Point Pkwy Ste 108, O Fallon, MO 63368
Phone: 636-344-2400    Fax: 636-344-2401
Neal Holzum, MD
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Medicare: Accepting Medicare Assignments
Practice Location: 2 Progress Point Ct, Ste 101a, O Fallon, MO 63368
Phone: 636-236-9945    

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.