Howard Guan, MD - Medicare Ophthalmology in San Marcos, CA

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Howard Guan, MD is a medicare enrolled "Ophthalmology - Glaucoma Specialist" physician in San Marcos, California. He went to Loma Linda University School Of Medicine and graduated in 2010 and has 16 years of diverse experience with area of expertise as Ophthalmology. He is a member of the group practice Tory Prestera Md Inc. and his current practice location is 340 Rancheros Drive, Suites 164/166, San Marcos, California. You can reach out to his office (for appointments etc.) via phone at (760) 598-0400.

Howard Guan is licensed to practice in California (license number A119766) 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 1134427636.

Contact Information

Howard Guan, MD
340 Rancheros Drive, Suites 164/166,
San Marcos, CA 92069
(760) 598-0400
(760) 290-7044

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Physician's Profile

Full NameHoward Guan
GenderMale
SpecialityOphthalmology
Experience16 Years
Location340 Rancheros Drive, San Marcos, California
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:
  • Howard Guan attended and graduated from Loma Linda University School Of Medicine in 2010
  NPI Data:
  • NPI Number: 1134427636
  • Provider Enumeration Date: 03/07/2011
  • Last Update Date: 10/21/2025
  Medicare PECOS Information:
  • PECOS PAC ID: 4385868256
  • Enrollment ID: I20150724011344

Medical Identifiers

Medical identifiers for Howard Guan such as npi, medicare ID, medicare PIN, medicaid, etc.
IdentifierTypeStateIssuer
1134427636NPI-NPPES

Medical Taxonomies and Licenses

TaxonomyTypeLicense (State)Status
207W00000XOphthalmology A119766 (California)Secondary
207WX0009XOphthalmology - Glaucoma Specialist A119766 (California)Primary

Group Practice Association

Group Practice NameGroup PECOS PAC IDNo. of Members
Tory Prestera Md Inc.00425945252

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. Howard Guan allows following entities to bill medicare on his behalf.
Entity NameFaculty Physicians And Surgeons Of Llusm
Entity TypePart B Supplier - Clinic/group Practice
Entity IdentifiersNPI Number: 1205009917
PECOS PAC ID: 1153227814
Enrollment ID: O20031211000981
Entity NameEmergency And Acute Care Medical Corporation
Entity TypePart B Supplier - Clinic/group Practice
Entity IdentifiersNPI Number: 1437103942
PECOS PAC ID: 9537108279
Enrollment ID: O20050502000734
Entity NameTory Prestera Md Inc.
Entity TypePart B Supplier - Clinic/group Practice
Entity IdentifiersNPI Number: 1073970687
PECOS PAC ID: 0042594525
Enrollment ID: O20170228002703
Entity NameRsf Ophthalmology, Pc
Entity TypePart B Supplier - Clinic/group Practice
Entity IdentifiersNPI Number: 1497466767
PECOS PAC ID: 1759755986
Enrollment ID: O20230329002713

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. Howard Guan 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
Howard Guan, MD
340 Rancheros Drive, Suites 164/166,
San Marcos, CA 92069

Ph: (760) 598-0400		Howard Guan, MD
340 Rancheros Drive, Suites 164/166,
San Marcos, CA 92069

Ph: (760) 598-0400

Reviews and Comments


Ophthalmology Doctors in San Marcos, CA

Dr. Lorne D. Kapner, M.D.
Ophthalmology
Medicare: Accepting Medicare Assignments
Practice Location: 838 Nordahl Rd Ste 220, San Marcos, CA 92069
Phone: 760-738-9985    Fax: 800-838-2695
Tory Prestera, MD.PHD
Ophthalmology
Medicare: Accepting Medicare Assignments
Practice Location: 340 Rancheros Drive, Suites 164/166, San Marcos, CA 92069
Phone: 760-598-0400    Fax: 760-290-7044

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.