William Lopez, M.D.
William Lopez, M.D. is a Preventive Medicine/Occupational Environmental Medicine Physician in Chicago, IL, registered under NPI 1811014228.
Getting there
The practice address on file is 900 E 103RD ST, Chicago, IL 60628. 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 |
|---|---|---|
| 036085602 | IL | Preventive Medicine/Occupational… primary |
This provider holds licence 036085602 issued in IL. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
This NPI does not appear in the PECOS Medicare enrolment file. Providers who do not bill Medicare — or who bill only through a group's enrolment — will not appear here. It is not a sign of any problem with the registration.
What Preventive Medicine/Occupational Environmental Medicine covers
A preventive medicine physician who specializes in preventive medicine/occupational-environmental medicine, which is focused on protecting the population from occupational and environmental conditions. NUCC Health Care Provider Taxonomy, code 2083P0500X
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 | 1811014228 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Mar 23, 2007 |
| Last updated | May 8, 2009 |
| Status | Active |
| Sole proprietor | No |
| Credential | M.D. |
| Practice address |
900 E 103RD ST Chicago, IL 60628 (615) 778-4066 |
| Mailing address |
5080 SPECTRUM DR SUITE 120 WEST Addison, TX 75001 |
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 | 8 | 1 | 1 | 0 | 1 | 4 | 2 | 2 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 8 | 2 | 1 | 0 | 1 | 8 | 2 | 4 |
Sum = 52 · next multiple of 10 = 60 · check digit = 8 · actual last digit = 8
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.