Merryalynn Sioson, MD
NPI 1558438457 · Family Medicine Physician · Anaheim, CA
Enrolled with Medicare as Practitioner - Family Practice · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Merryalynn Sioson, MD is a Family Medicine Physician provider in Anaheim, CA (NPI 1558438457).
Provider details
- NPI number
- 1558438457
- Entity type
- Individual
- Primary specialty
- Family Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Female
- Sole proprietor
- No
- License
- A69787 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
19 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 95 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Atorvastatin Calcium | 526 | 170 |
| Amlodipine Besylate | 426 | 127 |
| Losartan Potassium | 419 | 123 |
| Levothyroxine Sodium | 278 | 82 |
| Rosuvastatin Calcium | 225 | 73 |
| Hydrocodone/Acetaminophenbrand: Hydrocodone-Acetaminophen | 222 | 29 |
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-11-29
- Last updated
- 2021-12-01
Frequently asked questions
- What is Merryalynn Sioson's NPI number?
- Merryalynn Sioson's National Provider Identifier (NPI) is 1558438457, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Merryalynn Sioson's specialty?
- Merryalynn Sioson is listed in the NPPES registry with a primary specialty of Family Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Merryalynn Sioson located?
- Merryalynn Sioson's practice location on file with NPPES is 441 N Lakeview Ave, Anaheim, CA 92807-3028.
- What is Merryalynn Sioson's phone number?
- The practice phone number listed in the NPPES registry for Merryalynn Sioson is (888) 988-2800.
- Does Merryalynn Sioson accept Medicare?
- Merryalynn Sioson is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Merryalynn Sioson's NPI active?
- Yes — Merryalynn Sioson's NPI (1558438457) is active in the NPPES registry as of the last update on 2021-12-01.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.