Natalie Markwell, RADT 1
Natalie Markwell, RADT 1 is an Addiction (Substance Use Disorder) Counselor in Escondido, CA, registered under NPI 1003596867.
Getting there
Here is what surrounds this office in Escondido, based on OpenStreetMap data collected Oct 9, 2026. Parking is available about 0.24 mi away. There is EV charging 879 ft from the office — useful if you are driving in from out of town. The nearest transit stop is 463 ft away. A pharmacy sits 814 ft from the entrance (CVS Pharmacy), which helps if you leave with a prescription. If you arrive early, there is a coffee shop 296 ft away.
Getting here and what is nearby
Hotel Rodeway Inn 182 ft ~1 min
Transit 325 ft ~2 min
Coffee Starbucks 296 ft ~2 min
Transit 365 ft ~2 min
Restaurant Papa John's 415 ft ~2 min
245 West El Norte Parkway, Escondido 92026
Mo-Th 11:00-23:00; Fr-Sa 11:00-01:00; Su 11:00-23:00
Transit 463 ft ~2 min
Restaurant DQ Grill & Chill 630 ft ~3 min
Pharmacy CVS Pharmacy 814 ft ~4 min
EV charging 879 ft ~4 min
Parking 978 ft ~4 min
Parking 0.23 mi ~5 min
Grocery Vons 0.23 mi ~5 min
330 West El Norte Parkway, Escondido 92026
Mo-Su 06:00-23:00
Parking 0.24 mi ~5 min
Convenience 7-Eleven 0.28 mi ~6 min
Restaurant El Pollo Loco 0.28 mi ~6 min
350 West El Norte Parkway, Escondido 92026
Mo-Fr 09:30-22:30; Sa-Su 10:00-22:30
Gas station 7-Eleven 0.31 mi ~7 min
Convenience 7-Eleven 0.32 mi ~7 min
Convenience ampm 0.40 mi ~8 min
Gas station Arco 0.41 mi ~9 min
Distances are straight‑line estimates — walking routes may be longer. Hours and phone numbers can change; call ahead to confirm.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| R1503880423 | CA | Addiction (Substance Use Disorder)… primary |
This provider holds licence R1503880423 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 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 | 1003596867 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Jul 18, 2023 |
| Last updated | Jul 18, 2023 |
| Status | Active |
| Sole proprietor | No |
| Gender | Female |
| Credential | RADT 1 |
| Practice address |
1341 N ESCONDIDO BLVD Escondido, CA 92026 (760) 747-1015 |
| Mailing address |
30890 BARDMORE DR Temecula, CA 92592 |
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 | 9 | 6 | 8 | 6 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 0 | 0 | 3 | 1 | 9 | 3 | 8 | 3 |
Sum = 53 · next multiple of 10 = 60 · check digit = 7 · actual last digit = 7
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.