Justin Marasigan, MD

Medicare activity in 2024

Official CMS public-use data for Justin Marasigan, 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. Chronic care management services for two or more chronic conditions, additional 20 minutes of clinical staff time directed by health care professional, per calendar month (99439)764 services
2. Chronic care management services, first 20 minutes of clinical staff time directed by health care professional, per calendar month (99490)416 services
3. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)251 services
4. Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43239)136 services
5. New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more (99204)120 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 blood pressure75%
• High cholesterol75%
• Arthritis47%
• Diabetes44%
• Ischemic heart disease38%
• Chronic kidney disease32%

Hospitals where Justin Marasigan works

Medicare's Facility Affiliation Data lists Justin Marasigan 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.

• Community Memorial Hospital - VenturaVentura, CA · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 050394
• St Johns Regional Medical CenterOxnard, CA · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 050082

Practice locations

Addresses where Justin Marasigan is enrolled with Medicare (CMS data updated October 2, 2026).

• 2241 Wankel Way, Suite AOxnard, CA 93030 (805) 983‑0521
• 4005 Mission Oaks Blvd, Suite ACamarillo, CA 93012 (805) 484‑7921

Group practices

Medicare enrollment lists Justin Marasigan as a member of this group (CMS data updated October 2, 2026).

• Genesis Healthcare Partners PC228 clinicians in the group

Specialties

• Gastroenterologyprimary

Find other Gastroenterology doctors in California →

Other gastroenterologists in Oxnard

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

• Karen L. Simon, MD
• Hardeep M. Singh, MD
• Micha S. Rojany, MD
• Jay J. Guan, MD
• Shaham S. Mumtaz, MD
• Rukmini Enjamuri, MD
• Ashwinee S. Condon, MD

All gastroenterologists in Oxnard →

Other clinicians in Genesis Healthcare Partners PC

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

• Karen L. Simon, MD
• Janki Patel, MD
• Chi Lee, MD
• Zubin Shetty, MD
• Kathy Lu, NP
• Hardeep M. Singh, MD

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