Impact Endocrinology
Quick Facts
| Membership Price Range | $110/month or $630/6 months or $1,240/year | Diabetes in pregnancy: $1,200 | Thyroid disease in pregnancy: $950 |
| Practice Type | Direct Primary Care |
| Location | Carmel, central Indiana |
| Doctors | Elizabeth Grethen M.D., Endocrinology |
| Telehealth Type | Telemedicine video visits (available for patients in Indiana) |
| Telehealth Available | Yes |
About
At Impact Endocrinology, Dr. Elizabeth Grethen delivers direct care endocrinology to patients across central Indiana. The practice operates without insurance billing of any kind, including Medicare. Patients pay Dr. Grethen directly, which keeps the relationship straightforward and the billing transparent.
Dr. Grethen trained at Indiana University and spent more than 13 years at Ascension St. Vincent before opening Impact Endocrinology in Carmel. She holds double board certification in Endocrinology, Diabetes and Metabolism. Her clinical scope covers diabetes, thyroid disease, osteoporosis, adrenal and pituitary conditions, PCOS, calcium and bone disorders, and obesity. Appointments run 60 minutes, and same-day or next-day availability is common. Membership includes unlimited visits, priority scheduling, complimentary CGM and insulin pump downloads, and direct communication with Dr. Grethen by text, email, or phone. The practice sits in the Kirby Park East building on Carmel Drive, adjacent to the Monon Trail.
Details
Address
188 W. Carmel Drive, Carmel, IN 46032
Phone
(317) 660-1322Website
Visit websiteMembership
$110/monthly ($1,240/annual)
Membership Details
Membership includes unlimited appointments, priority scheduling, complimentary pump and CGM downloads, and unlimited direct communication with Dr. Grethen. First two months complimentary for patients who enroll at initial visit. Rejoin fee of $200 after a break. 5% discount per family member. Discounts applied if paid quarterly (2%), semi-annually (4%), or annually (6%). New patient visit: $395. Non-membership follow up: in-person 30 min $265, in-person 60 min $325, virtual 30 min $225, phone $300/hr.
Typical Appointment
60 minutes
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Frequently Asked Questions
Membership at Impact Endocrinology costs $110 per month or $1,240 per year. Patients who pay quarterly receive a 2% discount, semi-annual payment earns 4% off, and annual payment earns 6% off. Family members each receive a 5% discount. Patients who enroll at their initial visit receive their first two months complimentary.
Membership includes unlimited appointments, priority scheduling, complimentary CGM and insulin pump downloads, and unlimited direct communication with Dr. Grethen by text, email, or phone. Members also receive access to discounted wholesale lab tests and diabetes education at a reduced rate of $65 per hour.
No. Impact Endocrinology does not accept any insurance, including Medicare. Dr. Grethen has opted out of Medicare. Patients pay directly at the time of their appointment by credit card, check, or bank transfer. The practice does accept HSA and FSA payments.
No. Impact Endocrinology offers non-membership visit options. A new patient visit costs $395. Follow-up in-person visits run $265 for 30 minutes and $325 for 60 minutes. Virtual 30-minute visits cost $225, and phone consultations run $300 per hour. Dr. Grethen also offers one-time consultations and second opinions.
All new patients start with an initial consultation with Dr. Grethen. At that visit, she helps determine whether membership makes sense for your situation. New patients complete registration before scheduling, and the practice collects a deposit at registration. You can reach the practice by phone at (317) 660-1322 or through the contact form on the website.
Yes. Impact Endocrinology frequently offers same-day or next-day availability. Dr. Grethen keeps her patient panel smaller than a typical insurance-based specialty practice, which makes this level of access possible for members.
Yes. Dr. Grethen offers virtual visits for patients who prefer remote care. Virtual 30-minute appointments cost $225 for non-members and are available as part of the standard membership for enrolled patients.
Yes. A diabetes educator provides education services at Impact Endocrinology. Members pay $65 per hour for diabetes education sessions. Non-members pay $125 per hour.
Yes. Impact Endocrinology offers two short-term specialty memberships. The diabetes in pregnancy membership costs $1,200. The thyroid disease in pregnancy membership costs $950. These options serve patients who need focused endocrine support during pregnancy without committing to a full ongoing membership.
Yes. Dr. Grethen offers body composition analysis using bioimpedance technology through InBody testing. This service helps assess metabolic health beyond standard weight measurements and informs treatment planning for conditions like obesity and metabolic syndrome.
Practice last updated August 17, 2026