Dennis Mcmahon, M.D.
Dennis Mcmahon, M.D. is a Plastic Surgery Physician in San Francisco, CA, registered under NPI 1821277831. NPPES records them as a sole proprietor, meaning the practice is not incorporated as a separate legal entity.
Getting there
The practice address on file is 45 CASTRO ST SUITE 121, San Francisco, CA 94114. 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 |
|---|---|---|
| A88141 | CA | Plastic Surgery Physician primary |
This provider holds licence A88141 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 Plastic Surgery covers
A plastic surgeon deals with the repair, reconstruction or replacement of physical defects of form or function involving the skin, musculoskeletal system, craniomaxillofacial structures, hand, extremities, breast and trunk and external genitalia or cosmetic enhancement of these areas of the body. Cosmetic surgery is an essential component of plastic surgery. The plastic surgeon uses cosmetic surgical principles to both improve overall appearance and to optimize the outcome of reconstructive procedures. The surgeon uses aesthetic surgical principles not only to improve undesirable qualities of normal structures but in all reconstructive procedures as well. NUCC Health Care Provider Taxonomy, code 208200000X
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 | 1821277831 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Oct 25, 2007 |
| Last updated | Oct 24, 2008 |
| Status | Active |
| Sole proprietor | Yes |
| Credential | M.D. |
| Practice address |
45 CASTRO ST SUITE 121 San Francisco, CA 94114 (415) 565-6897 Fax (415) 864-1654 |
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 | 2 | 1 | 2 | 7 | 7 | 8 | 3 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 8 | 4 | 1 | 4 | 7 | 5 | 8 | 6 |
Sum = 69 · next multiple of 10 = 70 · check digit = 1 · actual last digit = 1
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.