Isabella Murphy
Isabella Murphy is an Addiction (Substance Use Disorder) Counselor in Antioch, CA, registered under NPI 1003571811. NPPES records them as a sole proprietor, meaning the practice is not incorporated as a separate legal entity.
Getting there
Here is what surrounds this office in Antioch, based on OpenStreetMap data collected Oct 7, 2026. Parking is available about 0.48 mi away. The nearest transit stop is 0.21 mi away, served by A Street & East 19th Street.
Getting here and what is nearby
Transit West 18th Street & D Street 297 ft ~2 min
Transit West 18th Street & D Street 403 ft ~2 min
Grocery Cielo Supermarker 665 ft ~3 min
1818 A Street, Antioch 94509
Restaurant Juarez Mexican Restaurant 917 ft ~4 min
1806 A Street, Antioch 94509
Restaurant Taco Bell 0.20 mi ~5 min
Transit A Street & East 19th Street 0.21 mi ~5 min
Restaurant Los Caporales Taqueria 0.33 mi ~7 min
1645 A Street, Antioch 94509
Mo-Fr 09:00-20:30; Sa-Su 08:00-21:00
Parking 0.36 mi ~8 min
Parking 0.48 mi ~10 min
Distances are straight‑line estimates — walking routes may be longer. Hours and phone numbers can change; call ahead to confirm.
Credentials and Medicare
NPPES does not list a state licence number for this record. That is not unusual — organizations and some provider types are not required to file one. Verify current licensure with the relevant state board before care.
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 Addiction (Substance Use Disorder) covers
Definition to come... NUCC Health Care Provider Taxonomy, code 101YA0400X
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 | 1003571811 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Nov 5, 2021 |
| Last updated | Nov 5, 2021 |
| Status | Active |
| Sole proprietor | Yes |
| Gender | Female |
| Practice address |
1915 D ST Antioch, CA 94509 (925) 754-3673 |
| Mailing address |
1342 TIFFANY DR Brentwood, CA 94513 |
| Other identifiers |
12314016
· Other (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 | 0 | 0 | 3 | 5 | 7 | 1 | 8 | 1 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 0 | 0 | 3 | 1 | 7 | 2 | 8 | 2 |
Sum = 49 · next multiple of 10 = 50 · 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.