Mark Ridder, M.D.
NPI 1821542739 · Infectious Disease Physician · Marshfield, WI
Enrolled with Medicare as Practitioner - Infectious Disease · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Mark Ridder, M.D. is a Infectious Disease Physician provider in Marshfield, WI (NPI 1821542739).
Provider details
- NPI number
- 1821542739
- Entity type
- Individual
- Primary specialty
- Infectious Disease PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- 68148 (WI)
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
9 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
2 documented practice locations
- Medicare service volume (vs. specialty peers)28% of score
971 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) |
|---|---|---|
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 35 Minutes99232 | 464 | $73 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 50 Minutes99233 | 159 | $110 |
| Initial Hospital Care With Moderate Level of Medical Decision Making, If Using Time, at Least 75 Minutes99223 | 156 | $160 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 95 | $90 |
| Initial Hospital Care With Straightforward Or Low-Level Medical Decision Making, If Using Time, at Least 55 Minutes99222 | 47 | $121 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 17 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Cephalexin | 78 | 26 |
| Bictegrav/Emtricit/Tenofov Alabrand: Biktarvy | 50 | — |
| Penicillin V Potassium | 48 | 11 |
| Sulfamethoxazole/Trimethoprimbrand: Sulfamethoxazole-Trimethoprim | 43 | 19 |
| Ceftriaxone Sodiumbrand: Ceftriaxone | 37 | 13 |
| Amoxicillin/Potassium Clavbrand: Amoxicillin-Clavulanate Potass | 27 | 20 |
| Doxycycline Hyclate |
Practice location
Mailing address
Additional practice locations (1)
- M120 Highway 97Marshfield, WI 54449Phone: (715) 502-5575
Registry dates
- Enumerated
- 2016-08-09
- Last updated
- 2022-12-12
- Certified
- 2022-12-12
Frequently asked questions
- What is Mark Ridder's NPI number?
- Mark Ridder's National Provider Identifier (NPI) is 1821542739, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Mark Ridder's specialty?
- Mark Ridder is listed in the NPPES registry with a primary specialty of Infectious Disease Physician (Allopathic & Osteopathic Physicians).
- Where is Mark Ridder located?
- Mark Ridder's practice location on file with NPPES is 1000 N Oak Ave, Marshfield, WI 54449-5703.
- What is Mark Ridder's phone number?
- The practice phone number listed in the NPPES registry for Mark Ridder is (715) 387-5511.
- Does Mark Ridder accept Medicare?
- Mark Ridder is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Mark Ridder's NPI active?
- Yes — Mark Ridder's NPI (1821542739) is active in the NPPES registry as of the last update on 2022-12-12.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.