Gary Nicolaisen, MD
Gary Nicolaisen, MD is an Urology Physician in San Rafael, CA, registered under NPI 1598849572.
Getting there
The practice address on file is 99 MONTECILLO RD, San Rafael, CA 94903. 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 |
|---|---|---|
| G42970 | CA | Urology Physician primary |
This provider holds licence G42970 issued in CA. 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 Urology covers
A urologist manages benign and malignant medical and surgical disorders of the genitourinary system and the adrenal gland. This specialist has comprehensive knowledge of and skills in endoscopic, percutaneous and open surgery of congenital and acquired conditions of the urinary and reproductive systems and their contiguous structures. NUCC Health Care Provider Taxonomy, code 208800000X
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 | 1598849572 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Oct 25, 2006 |
| Last updated | Jul 8, 2007 |
| Status | Active |
| Sole proprietor | No |
| Credential | MD |
| Practice address |
99 MONTECILLO RD San Rafael, CA 94903 (415) 444-2000 |
| Mailing address |
1800 HARRISON ST FL 7 Oakland, CA 94612 |
| Other identifiers |
00G429700
(CA) |
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 | 5 | 9 | 8 | 8 | 4 | 9 | 5 | 7 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 5 | 9 | 8 | 7 | 4 | 9 | 5 | 5 |
Sum = 78 · next multiple of 10 = 80 · check digit = 2 · actual last digit = 2
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.