Oksana B. Hirniak, DO

Medicare activity in 2024

Official CMS public-use data for Oksana B. Hirniak, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.

Most frequent services

1. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)225 services
2. Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit (G0439)19 services
3. Screening mammography (77067)14 services
4. Dxa bone density measurement of hip, pelvis, spine (77080)13 services
5. Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)11 services

Chronic conditions among these patients

Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).

• High cholesterol75%
• High blood pressure72%
• Arthritis32%
• Diabetes26%
• Osteoporosis18%
• Anxiety15%

Hospitals where Oksana B. Hirniak works

Medicare's Facility Affiliation Data lists Oksana B. Hirniak at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.

• Palomar Health Downtown CampusEscondido, CA · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 050115

Practice locations

Addresses where Oksana B. Hirniak is enrolled with Medicare (CMS data updated October 2, 2026).

• 277 Rancheros Dr, Suite 100San Marcos, CA 92069 (866) 228‑2236

Group practices

Medicare enrollment lists Oksana B. Hirniak as a member of this group (CMS data updated October 2, 2026).

• Graybill Medical Group Inc104 clinicians in the group

Specialties

• Family Practiceprimary
• Osteopathic Manipulative Medicinealso

Find other Family Practice doctors in California →

Other family doctors in San Marcos

Clinicians with the same Medicare primary specialty in San Marcos, CA — not a recommendation.

• Carolene G. Madden, MD
• Crystal D. Nguyen, MD
• Neil L. Halim, MD
• Leanne M. Zakrzewski, MD
• Adrienne M. Law, DO
• Lester M. Deguzman, MD
• Alexander C. Eller, MD
• Elisa A. Wilson, MD

All family doctors in San Marcos →

Other clinicians in Graybill Medical Group Inc

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

• Erin S. Pollett, PA
• Indira Molai, MD
• Juan Carlos T. Franco, MD
• Paul V. Polishuk, MD
• Saurabh Shah, MD
• Anna R. Foraci, DO

Clinician information

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
6. Medicare Care Compare — official Medicare tool to look up clinicians