MRS. KAREN JANET TERWILLIGER MS, APRN, AGPCNP-BC
NPI 1245616705
Nurse Practitioner - Gerontology in Mystic, CT
NPI Status: Active since August 07, 2015
Some details in this NPI profile have been updated in the NPI registry within the last 30 days.
- Individual
- Female
- Nurse Practitioner
- Gerontology
- PECOS Enrolled
About KAREN TERWILLIGER
This page provides the complete NPI Profile along with additional information for Karen Terwilliger, a provider established in Mystic, Connecticut with a medical specialization in Nurse Practitioner, focusing in gerontology . The healthcare provider is registered in the NPI registry with number 1245616705 assigned on August 2015. The practitioner's primary taxonomy code is 363LG0600X with license number 6220 (CT). The provider is registered as an individual and her NPI record was last updated June 2026.
- NPI
- 1245616705
- Provider Name
- MRS. KAREN JANET TERWILLIGER MS, APRN, AGPCNP-BC
- Gender
- Female
- Entity Type
- Individual
- Location Address
- 3 HERON RD MYSTIC, CT 06355
- Location Phone
- (401) 497-6799
- Mailing Address
- 23 OLD VOLUNTOWN RD GRISWOLD, CT 06351
- Mailing Phone
- (401) 497-6799
- Is Sole Proprietor?
- No
- Enumeration Date
- 08-07-2015
- Last Update Date
- 06-02-2026
- Code Navigator
A nurse practitioner (NP) like Karen Terwilliger is an experienced registered nurse with a master’s or doctoral degree and advanced clinical training. Nurse practitioners can work in many different specialties including primary care, pediatrics, cardiology, emergency, women’s health, oncology or geriatrics. Nurse practitioners provide services like physical exams, order laboratory tests, manage diseases, write prescriptions, etc.
Location Map
Secondary Locations
- 112 Mansfield Ave
Willimantic, CT 06226
(860) 456-6965 - 111 Salem Tpke
Norwich, CT 06360
(860) 425-8700
Specialty - Primary Taxonomy
The NPI enumerator requires providers to submit at least one taxonomy code. A taxonomy code is a unique 10-character code that describes the healthcare provider type, classification, and the area of specialization. There could be only one primary taxonomy code per NPI record. For individual NPIs the license data is associated to the taxonomy code.
- Classification
Nurse Practitioner Gerontology
- Taxonomy Code
- 363LG0600X
- Type
- Physician Assistants & Advanced Practice Nursing Providers
- License No.
- 6220
- License State
- CT
Secondary Taxonomies
The provider has reported to the NPI enumerator additional taxonomy codes. Multiple taxonomy codes may represent subspecialties or other areas of specialization the provider maybe licensed to practice.
| No. | Taxonomy Code | Type | Classification / Specialization |
License No. (State) |
|---|---|---|---|---|
| 1 | 363LP2300X | Physician Assistants & Advanced Practice Nursing Providers | Nurse Practitioner | 6220 (CT) |
Medicare Participation & PECOS Enrollment Status
Karen Terwilliger is enrolled in PECOS and is eligible to order or refer health care services for Medicare patients. The provider is eligible to order or refer: Part B Clinical Laboratory and Imaging, Durable Medical Equipment (DME), a Home Health Agency (HHA) and Power Mobility Devices.
What is PECOS?
PECOS is the online Medicare enrollment management system or Provider, Enrollment, Chain and Ownership System. The PECOS system is a database of providers who have registered with CMS as providers or suppliers. PECOS is the primary source of information about verified Medicare professionals. Providers that want to participate in this program need to enroll in PECOS with their NPI number to avoid denied claims.
Is the provider registered in PECOS? Yes
Eligible to Order or Refer Part B Clinical Laboratory and Imaging: Yes
Eligible to Order or Refer Durable Medical Equipment (DMEPOS): Yes
Eligible to Order or Refer a Home Health Agency (HHA): Yes
Eligible to Order or Refer Power Mobility Devices: Yes
Areas of Expertise
The following services and procedures, recently provided to Medicare patients, illustrate the range of care this provider offers. This list reflects the variety of services available to all patients visiting the practice and is based on 2022 Medicare dataset. In general, the more frequently a provider treats specific conditions or performs particular procedures, the more experienced they become in addressing similar patient needs. The provider has delivered many of the services listed below to Medicare patients. Please note that this list does not include services provided to patients who are not covered by Medicare.
Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit
Initial nursing facility care with moderate level of medical decision making, per day, if using time, at least 35 minutes
Initial nursing facility care with straightforward or low level of medical decision making, per day, if using time, at least 25 minutes
Removal of skin and tissue, 20.0 sq cm or less
Residence visit for established patient with low level of medical decision making, per day, if using time, at least 30 minutes
Residence visit for established patient with moderate level of medical decision making, per day, if using time, at least 40 minutes
Subsequent nursing facility care with moderate level of medical decision making, per day, if using time, at least 30 minutes
Subsequent nursing facility care with straightforward level of medical decision making, per day, if using time, 20 minutes or more
Subsequent nursing facility care with straightforward level of medical decision making, per day, if using time, at least 10 minutes
An annual wellness visit is a yearly appointment with your primary care provider to create or update a personalized prevention plan. This plan helps prevent illness based on your current health and risk factors. It's a subsequent visit, meaning it follows an initial assessment.
This service was performed 12 times for 12 patientsAn initial nursing facility visit per day is a service where a healthcare professional spends about 35 minutes assessing a patient's health status. This includes reviewing medical history, conducting a physical exam, and developing a care plan based on the patient's needs.
This service was performed 40 times for 40 patientsAn initial nursing facility visit is a daily check-up to monitor your health status. This service, lasting typically 25 minutes, involves a nurse assessing your overall wellbeing, discussing concerns, and updating your care plan as needed.
This service was performed 29 times for 29 patientsThis procedure involves the surgical removal of skin and tissue, up to 20.0 square cm in size. It's often performed to treat conditions like skin cancer or to remove moles, warts, and other skin lesions. The area is numbed and the unwanted tissue is carefully cut out.
This service was performed 62 times for 18 patientsAn established patient home visit is a 25-minute appointment where a healthcare provider visits you at your home. This service is for patients who have previously been seen by the provider. It includes a check-up and discussion about your health concerns.
This service was performed 53 times for 23 patientsAn established patient home visit is a medical appointment conducted at your home, typically lasting around 40 minutes. This service is ideal for patients who may find it difficult to travel to a healthcare facility. During this visit, a healthcare professional will evaluate your health status, manage your care, and answer any health-related questions you may have.
This service was performed 70 times for 31 patientsA follow-up nursing facility visit per day is a daily check-in by a healthcare professional. This 25-minute visit typically involves monitoring your health progress, addressing any concerns, and adjusting treatment plans as necessary. It's a vital part of ensuring your ongoing wellbeing.
This service was performed 85 times for 25 patientsA follow-up nursing facility visit per day is a daily check-up service provided by healthcare professionals. It lasts around 15 minutes and involves assessing your health status, monitoring your recovery progress, and addressing any concerns you may have about your health or treatment.
This service was performed 451 times for 89 patientsA follow-up nursing facility visit per day typically lasts about 10 minutes. This service involves a healthcare professional checking on your health status, answering any questions you may have, and monitoring your progress. This routine check ensures your recovery is on track and any concerns are addressed promptly.
This service was performed 191 times for 60 patientsPhysician Visit Costs
The pricing information below displays the copayment minimum, maximum and average amount that patients under Medicare are charged when visiting this provider as a new or established patient. Please keep in mind that these prices are just for reference purposes, and the actual prices charged by the provider might be different.
For patients covered under private health plans the prices below are also useful as healthcare pricing for private insurance is usually established as a function of Medicare prices. Private insurance covered patients should check their individual plans to determine the exact pricing.
The prices below reflect the costs for new and established patients in the 06355 ZIP code area.
New Patients Visit Costs *
The most utilized procedure code for new patients office visits is 99203
- Average New Patient Price $93.86
- Minimum New Patient Price $60.82
- Maximum New Patient Price $183.1
- Average New Patient Copayment $23.46
- Minimum New Patient Copayment $15.2
- Maximum New Patient Copayment $45.77
Established Patients Visit Costs *
The most utilized procedure code for established patients office visits is 99214
- Average Established Patient Price $106.68
- Minimum Established Patient Price $19.76
- Maximum Established Patient Price $149.26
- Average Established Patient Copayment $26.67
- Minimum Established Patient Copayment $4.94
- Maximum Established Patient Copayment $37.31
* The physician office visit costs information is generated by statistical analysis of similar providers in the same geographical area. The pricing information above IS NOT the amount charged by this provider.
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NPI NPI Number Validation
How NPI Validation Works
The NPI validation process uses the ISO-standard Luhn algorithm, a mathematical "handshake", to ensure that a provider's 10-digit ID is authentic and free of common typing errors.
To verify the NPI 1245616705, we treat the final digit (5) as the Check Digit—the target answer we need to reach. The process begins by taking the first nine digits and adding a constant value of 24, which accounts for the "80840" prefix required for all U.S. health identifiers. We then double every other digit starting from the right and sum the individual digits of those results together. For this specific NPI, that total comes to 55. The final step is to find the difference between that total and the next multiple of ten (60 - 55 = 5).
Digit-by-digit view
Use the first nine digits for the calculation. Starting from the right, double every other digit. The last digit is the check digit and is not part of the calculation.
Step 1: Double every other digit from the right
Starting with the rightmost digit of the first nine digits, double every other value. If doubling creates a two-digit number, add those digits together.
Step 2: Add all digits plus the NPI constant
Add the transformed values, the unchanged digits, and the constant 24.
Step 3: Find the amount needed to reach the next multiple of 10
The next multiple of ten after 55 is 60. The difference is the calculated check digit.
Other Providers at the Same Location
The following 7 providers are registered at the same or a nearby location.
MYSTIC, CT 06355
MYSTIC, CT 06355
Frequently Asked Questions
The NPI number assigned to this healthcare provider is 1245616705, enumerated as an "individual" on August 07, 2015.
The provider is located at 3 HERON RD MYSTIC, CT 06355 and the phone number is (401) 497-6799.
Nurse Practitioner with taxonomy code 363LG0600X and a focus in Gerontology.