Christopher Karalekas, O.D.
Christopher Karalekas, O.D. is a provider specialising in Optometrist in Lowell, MA, registered under NPI 1043212087. This provider registers 3 separate taxonomy codes, which usually means they practise across more than one recognised specialty.
Getting there
The practice address on file is 850 CHELMSFORD ST, Lowell, MA 01851. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| 3863 | MA | Optometrist primary |
| 3863 | MA | Low Vision Rehabilitation Optometrist |
| 3863 | MA | Corneal and Contact Management Optometrist |
This provider holds licence 3863 issued in MA. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
- Status
- Approved
- Provider type
- Practitioner - Optometry
- PAC ID
- 7719041557
Medicare enrolment is recorded as approved under the provider type Practitioner - Optometry. This means the provider is enrolled to bill Medicare, though it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.
What Optometrist covers
Doctors of optometry (ODs) are the primary health care professionals for the eye. Optometrists examine, diagnose, treat, and manage diseases, injuries, and disorders of the visual system, the eye, and associated structures as well as identify related systemic conditions affecting the eye. An optometrist has completed pre-professional undergraduate education in a college or university and four years of professional education at a college of optometry, leading to the doctor of optometry (O.D.) degree. Some optometrists complete an optional residency in a specific area of practice. Optometrists are eye health care professionals state-licensed to diagnose and treat diseases and disorders of the eye and visual system. NUCC Health Care Provider Taxonomy, code 152W00000X
All registered taxonomy codes
This provider registers 3 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 152W00000X | Optometrist | 3863 | MA | primary |
| 152WL0500X | Low Vision Rehabilitation Optometrist Low Vision Rehabilitation | 3863 | MA | |
| 152WC0802X | Corneal and Contact Management Optometrist Corneal and Contact Management | 3863 | MA |
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.
| NPI | 1043212087 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Aug 10, 2005 |
| Last updated | Sep 19, 2012 |
| Status | Active |
| Sole proprietor | No |
| Credential | O.D. |
| Practice address |
850 CHELMSFORD ST Lowell, MA 01851 (978) 452-0127 Fax (978) 452-1749 |
| Mailing address |
291 DALE ST Waltham, MA 02451 |
| Other identifiers |
31932
· FALLON HEALTH PLAN (MA) 365495 · HEALTH SOURCE MASS (MA) 980956 · NETWORK HEALTH (MA) 0006473 · NEIGHBORHOOD HEALTH PLAN (MA) 0369365 (MA) 151430 · HARVARD COMMUNITY HP (MA) 21613 · ANTHEM BC/BS (NH) 7625 · DAVIS VISION (MA) B20884301 · CIGNA W16129 · HMOBLUE/MASS. (MA) W16129 · BC/BS OF MASS. (MA) 042489265 · PHCS (MA) W20210 · BC/BS INDEMINITY (MA) 759053 · TUFTS HEALTH PLAN (MA) |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 0 | 4 | 3 | 2 | 1 | 2 | 0 | 8 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 0 | 8 | 3 | 4 | 1 | 4 | 0 | 7 |
Sum = 53 · next multiple of 10 = 60 · check digit = 7 · actual last digit = 7
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.