Katherine Manasson, M.D.
NPI 1538178611 · Internal Medicine Physician · Mission Viejo, CA
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Katherine Manasson, M.D. is a Internal Medicine Physician provider in Mission Viejo, CA (NPI 1538178611).
Provider details
- NPI number
- 1538178611
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Female
- Sole proprietor
- No
- License
- A61594 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
19 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
179 Medicare services, 2024 (ranked within specialty)
Medicare volume is ranked against active providers in the same specialty. 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 does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 83 | $138 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 56 | $97 |
| Annual Wellness Visit, Includes a Personalized Prevention Plan of Service (pps), Subsequent VisitG0439 | 40 | $140 |
Typical Medicare-allowed amounts for these services range $97–$140 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, not a price quote and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 57 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Levothyroxine Sodium | 250 | 52 |
| Atorvastatin Calcium | 221 | 60 |
| Amlodipine Besylate | 204 | 65 |
| Rosuvastatin Calcium | 125 | 38 |
| Alendronate Sodium | 93 | 25 |
| Metformin Hcl | 86 | 23 |
| Losartan Potassium |
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-08-06
- Last updated
- 2008-03-20
Frequently asked questions
- What is Katherine Manasson's NPI number?
- Katherine Manasson's National Provider Identifier (NPI) is 1538178611, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Katherine Manasson's specialty?
- Katherine Manasson is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Katherine Manasson located?
- Katherine Manasson's practice location on file with NPPES is 26732 Crown Valley Pkwy, Mission Viejo, CA 92691-6306.
- What is Katherine Manasson's phone number?
- The practice phone number listed in the NPPES registry for Katherine Manasson is (949) 348-1085.
- Does Katherine Manasson accept Medicare?
- Katherine Manasson is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Katherine Manasson's NPI active?
- Yes — Katherine Manasson's NPI (1538178611) is active in the NPPES registry as of the last update on 2008-03-20.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.