Quick answers
- Which hospitals does John Ioannou work at?
- Medicare's official clinician data lists John Ioannou at 3 hospitals: Chsli St Joseph Hospital, Mercy Medical Center and Mount Sinai South Nassau. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does John Ioannou see patients?
- Medicare's clinician data lists 2 practice locations, including Manhasset, NY and Bayside, NY. Call before your visit to confirm the address.
- What is John Ioannou's specialty?
- Medicare lists Nephrology as the primary specialty, and also Internal Medicine.
- Does John Ioannou accept Medicare assignment?
- Yes. Medicare's clinician data says John Ioannou accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
- Does John Ioannou offer telehealth?
- Medicare's clinician data says John Ioannou offers telehealth services. Ask the office which visits can be done by video or phone.
- What is the phone number for John Ioannou?
- (516) 407-2727, as listed in official Medicare / NPI Registry data.
- What is John Ioannou's NPI number?
- 1851330328. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where John Ioannou works
Medicare's Facility Affiliation Data lists John Ioannou at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Chsli St Joseph HospitalBethpage, NY · Acute Care Hospital · CCN 330332
- Mercy Medical CenterRockville Centre, NY · Acute Care Hospital · CCN 330259
- Mount Sinai South NassauOceanside, NY · Acute Care Hospital · CCN 330198
Practice locations
Addresses where John Ioannou is enrolled with Medicare (CMS data updated 2026-10-02).
- 1129 Northern Blvd, Suite 101Manhasset, NY 11030 (516) 407‑2727
- 20110 Northern Blvd, Suite 304Bayside, NY 11361 (516) 407‑2727
Group practices
Medicare enrollment lists John Ioannou as a member of this group (CMS data updated 2026-10-02).
- Prine Health Medical Group, PLLC77 clinicians in the group
Specialties
- Nephrologyprimary
- Internal Medicinealso
Other nephrologists in Manhasset
Clinicians with the same Medicare primary specialty in Manhasset, NY — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | Icahn School Of Medicine At Mount Sinai |
| Graduation year | 2001 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1851330328 |
| Corrections | Report an error or suggest an update → |
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
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
- National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians