Michael Main, MD
Michael Main, MD is an Allergy & Immunology (Internal Medicine) Physician in San Francisco, CA, registered under NPI 1649833005.
Getting there
The practice address on file is 45 CASTRO ST, 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 |
|---|---|---|
| A178576 | CA | Allergy & Immunology (Internal Medicine)… primary |
This provider holds licence A178576 issued in CA. 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 - Allergy/immunology
- PAC ID
- 9638610132
- Enrollment ID
- I20240924004438
Medicare enrolment is recorded as approved under the provider type Practitioner - Allergy/immunology. Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.
What Allergy & Immunology covers
An internist doctor of osteopathy that specializes in the treatment of allergy and immunologic disorders. A doctor of osteopathy that is board eligible/certified by the American Osteopathic Board of Internal Medicine can obtain a Certificate of Special Qualifications in the field of Allergy & Immunology. NUCC Health Care Provider Taxonomy, code 207RA0201X
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 | 1649833005 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Apr 20, 2019 |
| Last updated | Oct 13, 2024 |
| Status | Active |
| Sole proprietor | No |
| Credential | MD |
| Practice address |
45 CASTRO ST San Francisco, CA 94114 (702) 882-5285 |
| Mailing address |
8 BUCHANAN ST UNIT 605 San Francisco, CA 94102 |
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 | 6 | 4 | 9 | 8 | 3 | 3 | 0 | 0 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 6 | 8 | 9 | 7 | 3 | 6 | 0 | 0 |
Sum = 65 · next multiple of 10 = 70 · check digit = 5 · actual last digit = 5
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.