Errol Olwyn Grannum, MD - Medicare Ophthalmology in Mcallen, TX

Errol Olwyn Grannum, MD is a medicare enrolled "Ophthalmology" physician in Mcallen, Texas. He went to Yale University School Of Medicine and graduated in 1989 and has 35 years of diverse experience with area of expertise as Ophthalmology. He is a member of the group practice Alexander P. Sudarshan Md Pa and his current practice location is 1910 S 1st St, Mcallen, Texas. You can reach out to his office (for appointments etc.) via phone at (956) 687-3937.

Errol Olwyn Grannum is licensed to practice in Texas (license number K5972) 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 1508897935.

Contact Information

Errol Olwyn Grannum, MD
1910 S 1st St,
Mcallen, TX 78503-1255
(956) 687-3937
(956) 687-3938

Map and Direction




Physician's Profile

Full NameErrol Olwyn Grannum
GenderMale
SpecialityOphthalmology
Experience35 Years
Location1910 S 1st St, Mcallen, Texas
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:
  • Errol Olwyn Grannum attended and graduated from Yale University School Of Medicine in 1989
  NPI Data:
  • NPI Number: 1508897935
  • Provider Enumeration Date: 07/05/2006
  • Last Update Date: 07/08/2007
  Medicare PECOS Information:
  • PECOS PAC ID: 8022011915
  • Enrollment ID: I20060815000073

Medical Identifiers

Medical identifiers for Errol Olwyn Grannum such as npi, medicare ID, medicare PIN, medicaid, etc.
IdentifierTypeStateIssuer
1508897935NPI-NPPES

Medical Taxonomies and Licenses

TaxonomyTypeLicense (State)Status
207W00000XOphthalmology K5972 (Texas)Primary

Medical Facilities Affiliation

Facility NameLocationFacility Type
Rio Grande Regional HospitalMcallen, TXHospital

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. Errol Olwyn Grannum allows following entities to bill medicare on his behalf.
Entity NameErrol O Grannum
Entity TypePart B Supplier - Clinic/group Practice
Entity IdentifiersNPI Number: 1457377194
PECOS PAC ID: 4486657376
Enrollment ID: O20060815000068
Entity NameOphthalmic Consultants Of Texas P.a.
Entity TypePart B Supplier - Clinic/group Practice
Entity IdentifiersNPI Number: 1063513794
PECOS PAC ID: 7416055686
Enrollment ID: O20070612000372
Entity NameAlexander P. Sudarshan Md Pa
Entity TypePart B Supplier - Clinic/group Practice
Entity IdentifiersNPI Number: 1295014389
PECOS PAC ID: 7113199217
Enrollment ID: O20111014000325

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. Errol Olwyn Grannum 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
Errol Olwyn Grannum, MD
1910 S 1st St,
Mcallen, TX 78503-1255

Ph: (956) 687-3937
Errol Olwyn Grannum, MD
1910 S 1st St,
Mcallen, TX 78503-1255

Ph: (956) 687-3937

Reviews and Comments


Ophthalmology Doctors in Mcallen, TX

Vimal Sarup, MD
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Practice Location: 1309 E Ridge Rd Ste 1, Mcallen, TX 78503
Phone: 956-631-8875    Fax: 956-683-1502
Dr. Rachel Ann Gelman, M.D.
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Practice Location: 5201 N G St, Mcallen, TX 78504
Phone: 956-305-5795    Fax: 956-618-4639
Dr. Raul Adrian Pena, MD
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Practice Location: 1400 E Ridge Rd Ste 10, Mcallen, TX 78503
Phone: 956-661-8733    Fax: 956-661-8724
Dr. Melissa Ixcamey, M.D.
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Practice Location: 1309 E Ridge Rd Ste 1, Mcallen, TX 78503
Phone: 956-844-6440    
Cooper M Clark, D.O.
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Medicare: Accepting Medicare Assignments
Practice Location: 1309 E Ridge Rd, Suite 1, Mcallen, TX 78503
Phone: 956-631-8875    Fax: 956-682-6280
Dr. Wade Alan Graham, M.D.
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Medicare: Accepting Medicare Assignments
Practice Location: 1400 E Ridge Rd Ste 3, Mcallen, TX 78503
Phone: 956-429-4900    Fax: 956-429-4901
Dr. Nehal Rashmikant Patel, M.D.
Ophthalmology
Medicare: Accepting Medicare Assignments
Practice Location: 1309 East Ridge Road, Suite 1, Mcallen, TX 78503
Phone: 956-631-8875    Fax: 956-631-9134

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.