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Ophthalmology

John G. Allen, MD

Sees patients in Columbus, OH · Ohio

Summary

John G. Allen, MD (Ophthalmology) is enrolled with Medicare at 1 practice location in Columbus, OH. NPI 1821084096. Medicare data says the clinician accepts Medicare assignment. Source: CMS National Downloadable File, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about John G. Allen, joined by NPI number (data updated 2026-10-02). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

At a glance

OphthalmologyPrimary specialty
YesAccepts Medicare assignment
40Years since medical school (graduated 1986)
Ohio State University College Of MedicineMedical school
MaleGender (as listed)

Quick answers

Where does John G. Allen see patients?
Medicare's clinician data lists 1 practice location in Columbus, OH. Call before your visit to confirm the address.
What is John G. Allen's specialty?
Medicare lists Ophthalmology as the primary specialty.
Does John G. Allen accept Medicare assignment?
Yes. Medicare's clinician data says John G. Allen 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.
What is the phone number for John G. Allen?
(614) 267-4122, as listed in official Medicare / NPI Registry data.
What is John G. Allen's NPI number?
1821084096. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Practice locations

Addresses where John G. Allen is enrolled with Medicare (CMS data updated 2026-10-02).

Specialties

Find other Ophthalmology doctors in Ohio →

Other ophthalmologists in Columbus

Clinicians with the same Medicare primary specialty in Columbus, OH — not a recommendation.

All ophthalmologists in Columbus →

Clinician information

CredentialMD
Medical schoolOhio State University College Of Medicine
Graduation year1986
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1821084096
CorrectionsReport 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

  1. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  2. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  3. Medicare Care Compare — official Medicare tool to look up clinicians