KARTHIK IYER MD
NPI 1013203454
Internal Medicine - Critical Care Medicine in Festus, MO
About Karthik Iyer Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
KARTHIK IYER MD (NPI 1013203454) is an individual critical care medicine provider in Festus, Missouri, licensed in Missouri (2012041517) and active in the NPI registry since June 2011. He is enrolled in Medicare PECOS, is affiliated with Mercy Hospital Jefferson, and is a graduate of Other (2004).
NPPES Registry Identity
Specialties & Licenses
Accepted Insurance
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare and accepts Medicare assignment
Karthik Iyer Md is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.
Medicare Billing Reassignments
2Medicare enrollment records show Karthik Iyer reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Festus, MO 63028
- Reassigned Medicare billing, Missouri enrollment
- 299 clinicians in this Medicare group
Saint Louis, MO 63141
- Reassigned Medicare billing, Missouri enrollment
- 77 clinicians in this Medicare group
Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
Areas of Expertise CMS Part B claims 2
Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.
Hospital Affiliations CMS Care Compare
Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.
Mercy Hospital Jefferson
Acute Care Hospitals · Festus, MOPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 63028 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.
Other Providers at the Same Location NPPES 20
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
FESTUS, MO 63028
FESTUS, MO 63028
FESTUS, MO 63028
FESTUS, MO 63028
FESTUS, MO 63028
Frequently Asked Questions NPPES & CMS
Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.
What is Karthik Iyer's NPI number?
The NPI number for Karthik Iyer is 1013203454. It was assigned to this individual provider in the NPPES registry on June 23, 2011.
Where is Karthik Iyer located?
Karthik Iyer practices at 1400 Us Highway 61, Festus, MO 63028. The listed phone number is (636) 933-5337.
What is Karthik Iyer's specialty?
The primary specialty registered for this NPI is Internal Medicine, specializing in Critical Care Medicine, with taxonomy code 207RC0200X.
Is Karthik Iyer enrolled in Medicare?
Yes. Karthik Iyer is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.
Which organizations bill Medicare for Karthik Iyer's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Karthik Iyer reassigns Medicare benefits to 2 organizations: Mercy Clinic Adult Hospitalists- Jefferson, LLC (Festus, MO) and Mercy Clinic Adult Critical Care, LLC (Saint Louis, MO). Each reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Karthik Iyer's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Karthik Iyer accept?
Health plans from Anthem Blue Cross and Blue Shield list Karthik Iyer as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.
Is Karthik Iyer affiliated with any hospitals?
According to CMS data, Karthik Iyer is affiliated with Mercy Hospital Jefferson.
When was this NPI record last updated?
The NPPES record for Karthik Iyer was last updated on July 26, 2023. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.
# Karthik Iyer, MD · NPI 1013203454
Critical Care Medicine physician in Festus, Missouri. Individual provider, active in the CMS NPPES registry since June 23, 2011.
## Identity
- **NPI:** 1013203454 (Entity type: Individual)
- **Enumerated:** June 23, 2011
- **Primary specialty:** Internal Medicine - Critical Care Medicine · taxonomy 207RC0200X
- **State license:** 2012041517 (Missouri)
- **Sole proprietor:** No
## Practice location
- **Address:** 1400 US HIGHWAY 61, Festus, MO 63028-4100
- **Phone:** (636) 933-5337
## Medicare
- **Medicare:** Enrolled (PECOS); accepts Medicare assignment
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health, power mobility devices
- **Bills Medicare through:** 2 organizations under Medicare reassignment (form CMS-855R): Mercy Clinic Adult Hospitalists- Jefferson, LLC (NPI 1083052492, Festus, MO); Mercy Clinic Adult Critical Care, LLC (NPI 1730119421, Saint Louis, MO) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Other, class of 2004
## Record status
- **NPPES last updated:** July 26, 2023
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Source: [NPI Profile](https://npiprofile.com/npi/1013203454) · Data from the CMS NPPES public registry.