Sara Gretenhart, APNP
NPI 1821556317 · Family Nurse Practitioner · Cudahy, WI
Enrolled with Medicare as Practitioner - Nurse Practitioner · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Sara Gretenhart, APNP is a Family Nurse Practitioner provider in Cudahy, WI (NPI 1821556317).
Provider details
- NPI number
- 1821556317
- Entity type
- Individual
- Primary specialty
- Family Nurse PractitionerPhysician Assistants & Advanced Practice Nursing Providers
- Credential
- APNP
- Sex
- Female
- Sole proprietor
- Yes
- License
- 8850-33 (WI)
Specialties & taxonomies
Physician Assistants & Advanced Practice Nursing Providers
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
7 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
111 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
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 .
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 | 31 | $62 |
| Automated Urinalysis Test81003 | 24 | $2 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 23 | $73 |
| Ultrasound Measurement of Bladder Capacity After Voiding51798 | 18 | $10 |
| Initial Hospital Care With Straightforward Or Low-Level Medical Decision Making, If Using Time, at Least 55 Minutes99222 | 15 | $102 |
Typical Medicare-allowed amounts for these services range $2–$102 (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 · 8 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Tamsulosin Hcl | 41 | 27 |
| Ciprofloxacin Hcl | 40 | 38 |
| Hydrocodone/Acetaminophenbrand: Hydrocodone-Acetaminophen | 15 | 13 |
| Nitrofurantoin Monohyd/M-Crystbrand: Nitrofurantoin Mono-Macro | 14 | 14 |
| Oxybutynin Chloridebrand: Oxybutynin Chloride Er | 14 | — |
| Sulfamethoxazole/Trimethoprimbrand: Sulfamethoxazole-Trimethoprim | 13 | 12 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$228 across 9 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Registry dates
- Enumerated
- 2019-03-04
- Last updated
- 2019-03-04
Frequently asked questions
- What is Sara Gretenhart's NPI number?
- Sara Gretenhart's National Provider Identifier (NPI) is 1821556317, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Sara Gretenhart's specialty?
- Sara Gretenhart is listed in the NPPES registry with a primary specialty of Family Nurse Practitioner (Physician Assistants & Advanced Practice Nursing Providers).
- Where is Sara Gretenhart located?
- Sara Gretenhart's practice location on file with NPPES is 3108 E Hammond Ave, Cudahy, WI 53110-1811.
- What is Sara Gretenhart's phone number?
- The practice phone number listed in the NPPES registry for Sara Gretenhart is (414) 722-2947.
- Does Sara Gretenhart accept Medicare?
- Sara Gretenhart is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Sara Gretenhart's NPI active?
- Yes — Sara Gretenhart's NPI (1821556317) is active in the NPPES registry as of the last update on 2019-03-04.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.