ROBERT A ZAJAC (MD) – Infectious Disease Physician, NPI 1013907963

ROBERT A ZAJAC (MD) is a healthcare provider. based in San antonio, Texas. specializing in INFECTIOUS DISEASE. They hold the professional credentials MD. They hold a License No. H3973 (TX). The NPI Number for ROBERT A ZAJAC (MD) is 1013907963

Main info

Male
45 Years Of Experience
Accepts Medicare Assignment
Name
ROBERT A ZAJAC (MD)
NPI
1013907963
Phone
(210) 558-6288
Address
PO BOX 1346
Enumeration Date
24 October 2005
Last Update Date
8 August 2024

Doctor Profile

Medical School Name
LOUISIANA STATE UNIVERSITY SCHOOL OF MEDICINE IN NEW ORLEANS
Secondary Phone
2104812800
Graduation Year
1981 (45 years ago)
PAC ID
6103829726
Group Practice PAC ID
6204831498
Professional Enrollment ID
I20060821000053
Address ID
TX782584022SA150XXBLVD401
Telehealth
Yes
Data current as of
19 May 2026

Profile Insights

NPPES metrics only — not quality of care.

Methodology
Experience64
Completeness75
Years active:20State licenses:1Digital endpointsOther names

674 INFECTIOUS DISEASE in TX

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Provider Addresses for ROBERT A ZAJAC (MD)

  • San Antonio Post Office, 2nd Street, San Antonio, Socorro County, New Mexico, United States

    SAN ANTONIO, TX 782951346

    Phone: (210) 558-6288

    Fax: (210) 558-6289

    Type: Mailing

  • 150, East Sonterra Boulevard, San Antonio, Bexar County, Texas, 78258, United States

    SUITE 170

    SAN ANTONIO, TX 782584098

    Phone: (210) 481-2800

    Fax: (210) 481-2834

    Type: Location

NPPES updates history

No NPPES updates recorded for this provider.

Prescription Activity

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Open Payments (CMS)

CMS reports 60 Open Payments records for all available years, with a total value of $1,104.

Total Amount is formed as General ($1,104) + Research ($0) + Ownership ($0) = $1,104.

Last reported payment date: 2024-12-09 • Largest payer in this snapshot: ViiV Healthcare Company ($327).

Total Amount

$1,104

General + Research + Ownership

Payments

60

Total payment records

General Amount

$1,104

General payments

Research Amount

$0

Research funding

Ownership Amount

$0

Ownership interests

Ownership Count

0

Ownership records

Last Payment Date

2024-12-09

Latest reported date

Top Companies

Largest payers in this snapshot

View all Open Payments →|Open Payments Risk Radar →

Medicare Enrollment & Revalidation

Source: CMS public data · Not endorsed by CMS ·

Educational use only—not medical, billing, or legal advice.

PECOS enrollment status

Participating (accepts Medicare assignment)

Enrollment effective: 2006-08-21

PECOS data refreshed: 2026-05-27

Medicare revalidation (CMS due date list)

Due date not assigned yet

CMS is tracking this Medicare enrollment for revalidation, but has not published a due date.

Enrollment records

1

Earliest due date

Not assigned (TBD)

CMS data updated

2026-06-01

Revalidation progress

  1. Medicare enrolled
  2. On CMS revalidation list
  3. Due date assigned
  4. Revalidate in PECOS

CMS enrollment records

Enrollment IDTypeSpecialtyStateDue date
I20060821000053IInfectious DiseaseTXTBD

What to do next

  • No action required while the due date shows TBD.
  • Check the CMS Revalidation Lookup Tool periodically — CMS updates the list about every 60 days.
  • Do not submit a revalidation application in PECOS until CMS publishes a concrete due date.

Verify on CMS Revalidation Lookup Tool

Prepare CMS-855 application → · Look up this NPI in PECOS → · Verify on CMS PECOS

Medicare Utilization (FFS)

Source: CMS public data · Not endorsed by CMS · Beneficiary counts under 11 are suppressed in source data ·

Educational use only—not medical, billing, or legal advice.

Top Medicare procedures (2023) · refreshed 2026-05-27

HCPCSDescriptionServicesBeneficiariesMedicare allowed
J1561Injection, immune globulin, (gamunex-c/gammaked), non-lyophilized (e.g., liquid), 500 mg38,53038$0
J1556Injection, immune globulin (bivigam), 500 mg15,96030$0
96366Infusion into a vein for therapy, prevention, or diagnosis, each additional hour1,96045$0
99233Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes737263$0
99232Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes657235$0
View full utilization report →

Insurance plans in this area (ZIP 78295)

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Group practice members

Group practice members are other physicians who share the same Group Practice PAC ID with this doctor. When doctors form a group practice and register in PECOS as a single entity, they receive a shared identification number. This table lists all providers in the same group practice.
PAC ID: 6204831498View full group profile
NameSpecialtyState
Physician AssistantTX
Nurse PractitionerTX
-TX
Nurse PractitionerTX
Nurse PractitionerTX
Nurse PractitionerTX

Reviews

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Frequently asked questions

Does ROBERT A ZAJAC (MD) share an NPI with anyone else?
NPI numbers are unique to each provider or organization — ROBERT A ZAJAC (MD) uses 1013907963.
Is ROBERT A ZAJAC (MD) listed as active for patients and plans?
The listing shows ROBERT A ZAJAC (MD) as active in the NPI system.
What is ROBERT A ZAJAC (MD)'s specialty?
The listing groups ROBERT A ZAJAC (MD) with Infectious Disease Physician. Clinical services aligned with this taxonomy classification.
Where is ROBERT A ZAJAC (MD) based?
ROBERT A ZAJAC (MD) is tied to San Antonio, Texas in the data we show; additional addresses may exist on the full record.
Is specialty guaranteed by NPI alone?
Taxonomy selections describe intent; scope of practice still follows state law.

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