Ghassan Alzayer, MD

Medicare activity in 2024

Official CMS public-use data for Ghassan Alzayer, 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. Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes (99222)101 services
2. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)83 services
3. Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43239)66 services
4. New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more (99204)61 services
5. Biopsy of large bowel using a flexible endoscope (45380)40 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%
• Diabetes53%
• Arthritis43%
• Chronic kidney disease43%
• Ischemic heart disease38%

Hospitals where Ghassan Alzayer works

Medicare's Facility Affiliation Data lists Ghassan Alzayer 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.

• MedStar Washington Hospital CenterWashington, DC · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 090011

Practice locations

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

• 106 Irving St NW 4200, Mmg at WhcWashington, DC 20010 (202) 877‑2200

Group practices

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

• MedStar Medical Group II LLC3,767 clinicians in the group

Specialties

• Gastroenterologyprimary

Find other Gastroenterology doctors in District of Columbia →

Other gastroenterologists in Washington

Clinicians with the same Medicare primary specialty in Washington, DC — not a recommendation.

• Georgia A. Richards, MD
• Katherine A. Murphy, MD
• Xheni Deda, MD
• Abdalla Khouqeer, MD
• Marc L. Kozam, MD
• Adrienne Nguyen, MD
• Kevin Collier, MD
• Walid Chalhoub, MD

All gastroenterologists in Washington →

Other clinicians in MedStar Medical Group II LLC

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

• Erica Stoner, PA
• Peter T. Mulaikal, MD
• Onowu M. Imegwu, PA
• Jeffrey Lotlikar, MD
• Dan Kessler, MD
• Rita Poon, 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