Charles Ahrens, M.D.
NPI 1356540827 · Ophthalmology Physician · Duluth, MN
Enrolled with Medicare as Practitioner - Ophthalmology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Charles Ahrens, M.D. is a Ophthalmology Physician provider in Duluth, MN (NPI 1356540827).
Provider details
- NPI number
- 1356540827
- Entity type
- Individual
- Primary specialty
- Ophthalmology PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- 53850 (MN)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
18 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
1,610 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our .
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Imaging of Retina92134 | 359 | $31 |
| Established Patient Complete Exam of Visual System92014 | 270 | $88 |
| Injection of Drug Into Eye67028 | 255 | $105 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 239 | $69 |
| Measurement of Corneal Curvature and Depth of Eye92136 | 113 | $31 |
| Removal of Cataract With Insertion of Prosthetic Lens66984 | 103 | $511 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 16 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Latanoprost | 252 | 75 |
| Prednisolone Acetate | 153 | 126 |
| Timolol Maleate | 125 | 40 |
| Ketorolac Tromethamine | 115 | 87 |
| Ofloxacin | 99 | 82 |
| Tobramycin/Dexamethasonebrand: Tobramycin-Dexamethasone | 90 | 70 |
| Brimonidine Tartrate | 66 | 18 |
| Dorzolamide Hcl/Timolol Maleat |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$15 across 1 record (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Registry dates
- Enumerated
- 2007-07-16
- Last updated
- 2020-12-04
- Certified
- 2020-12-04
Frequently asked questions
- What is Charles Ahrens's NPI number?
- Charles Ahrens's National Provider Identifier (NPI) is 1356540827, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Charles Ahrens's specialty?
- Charles Ahrens is listed in the NPPES registry with a primary specialty of Ophthalmology Physician (Allopathic & Osteopathic Physicians).
- Where is Charles Ahrens located?
- Charles Ahrens's practice location on file with NPPES is 4190 Loberg Ave, Duluth, MN 55811-2652.
- What is Charles Ahrens's phone number?
- The practice phone number listed in the NPPES registry for Charles Ahrens is (218) 249-4600.
- Does Charles Ahrens accept Medicare?
- Charles Ahrens is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Charles Ahrens's NPI active?
- Yes — Charles Ahrens's NPI (1356540827) is active in the NPPES registry as of the last update on 2020-12-04.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.