Dr. Elizabeth Hart Mahon Williams, MD
- Medicare services, 2024
- 1,236
- Medicare patients, 2024
- 322
- Part D claims, 2024
- 9,135
- Publications
- 3
- Hospital affiliations
- 5
- Practice address
- 615 New Ballas Road, Saint Louis, MO 63141
- Practice phone
- Call (314) 251-6000
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Primary practice
Find Dr. Williams' professional email, personal email and mobile number
Dmand AI checks each channel through healthcare-specific waterfall enrichment. See what is on file with a free account, with practice phones, licenses and affiliations.
Dr. Elizabeth Hart Mahon Williams is an internist in Saint Louis, Missouri
Dr. Williams practices at Mercy Hospital St. Louis in Saint Louis, Missouri, part of Mercy.
Dr. Williams' NPI, 1952697468, was assigned on June 22, 2011. Dr. Williams graduated from University of Missouri, Columbia School of Medicine in 2011. Dr. Williams holds Missouri license 2011014989.
- NPI
- 1952697468NPI Registry (opens in a new tab)
- Medicare PAC ID
- 6709004849
- NPI enumeration date
- June 22, 2011
- NPI status
- Active
- Accepts Medicare assignment
- Yes
- Offers telehealth
- Yes
- Practice phone
- (314) 251-6000
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Female
- Estimated age
- 41
- Medical school graduation
- 2011
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; Dmand AI Affiliation Data; and Doctors and Clinicians National Downloadable File (CMS)
Dr. Elizabeth Hart Mahon Williams practices at Mercy Hospital St. Louis in Saint Louis, Missouri
Dr. Williams' primary practice is Mercy Hospital St. Louis, at 615 New Ballas Road, Saint Louis, MO 63141 in St. Louis County. The practice phone is (314) 251-6000.
- Mercy Hospital St. Louis615 New Ballas Road, Saint Louis, MO 63141 · St. Louis CountyPhone(314) 251-6000
Source: Dmand AI Affiliation Data
Dr. Elizabeth Hart Mahon Williams is affiliated with 7 sites of care and 2 medical groups
Dr. Williams' primary practice is Mercy Hospital St. Louis in Saint Louis, Missouri, part of Mercy. Dr. Williams is also affiliated with Missouri Baptist Medical Center. The medical group on file is Mercy Clinic East Communities. Dmand AI also links Dr. Williams to 3 more hospitals, 1 home health agency, 1 therapy and rehab clinic and 1 medical group, each named with a free account.
Sources: Dmand AI Affiliation Data; and Dmand AI Org Hierarchy Data
Dmand AI tracks the EHR system at Dr. Elizabeth Hart Mahon Williams' practice
Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Williams practices, 7 sites in all. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| Mercy Hospital St. Louis | Available with a free account |
| +6 more sites and 1 medical group | Available with a free account |
Source: Dmand AI Technology Install Data
For health IT teams
Dmand AI maps EHR vendors, IT decision makers and buying committees across Mercy and 6.2K+ hospitals, with verified contacts in the same login.
Dr. Elizabeth Hart Mahon Williams is one of 2,114 internists in Missouri
Internal medicine is Dr. Williams' primary specialty in the NPI Registry, under taxonomy code 207R00000X. Dr. Williams is licensed in Missouri.
Specialties and state licenses
- Internal medicine, MissouriPrimary
Internists near Dr. Williams
Counts of internists with a Dmand AI profile, by place and practice. Each opens the list.
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Peer Benchmarks
Dr. Elizabeth Hart Mahon Williams billed Medicare for 1,236 services in 2024
CMS data shows 1,236 Medicare services from Dr. Williams across 15 procedure codes in 2024, for 322 Medicare patients. Medicare paid $103,387 for them. Every service was in an office.
Dr. Williams' Medicare services by type, 2023 to 2024
- 2023
- 2024
- Office and hospital visits
- 2023: 5572024: 5651%
- Other services
- 2023: 4102024: 52027%
- Tests and treatments
- 2023: 1292024: 1225%
- Lab and pathology
- 2023: 02024: 29
Dr. Williams compared with the Missouri median for internists, 2024
- Dr. Williams
- Missouri median
- Medicare services
- 1,236vs 5302.3 times
- Medicare patients
- 322vs 21153% above
- Part D claims
- 8,480vs 32526.1 times
Medians across 2,076 internists in Missouri with Dmand AI profiles that report each measure.
Dr. Williams' most billed Medicare procedure codes, 2024
CMS publishes codes billed for 11 or more Medicare patients. Each label is the code family; CPT descriptions are licensed by the AMA.
Need commercial claims for Dr. Williams?
Medicare shows one payer. Book a meeting to get commercial claims data for Dr. Williams and other internists in Missouri.
Sources: Medicare Physician & Other Practitioners - by Provider and Service (CMS), 2024 data; and Dmand AI Peer Benchmarks
Dr. Elizabeth Hart Mahon Williams treated 322 Medicare patients in 2024, average age 74
CMS counts 322 Medicare patients who saw Dr. Williams in 2024. The largest group is 65 to 74, with 170 patients. 75% of them have high cholesterol, and 65% have high blood pressure. Their average risk score is 0.90, where 1.00 is the Medicare average.
Across all payers, Dmand AI patient panel data puts Dr. Williams' median patient age at 68, with 83% women.
Dr. Williams' Medicare patients by age, 2024
CMS leaves out age groups with fewer than 11 patients.
Dr. Williams' Medicare patients by sex, 2024
- Women24877%
- Men7423%
Chronic conditions among Dr. Williams' Medicare patients, 2024
- High cholesterol75%
- High blood pressure65%
- Arthritis49%
- Mood disorders29%
- Chronic kidney disease28%
- Depression28%
- Anxiety27%
- Cancer19%
Share of Medicare patients with each condition. A patient can have several.
Dr. Williams' patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 68
Patient panel by sex, all payers
- Women83%
- Men17%
Sources: Dmand AI Patient Panel Data; and Medicare Physician & Other Practitioners - by Provider (CMS), 2024 data
Dr. Elizabeth Hart Mahon Williams wrote 9,135 Medicare Part D claims in 2024
In 2024, Dr. Williams wrote 9,135 Medicare Part D claims for 741 patients. 89% of them were for generic drugs. CMS names the drug for 8,480 of them, across 123 drugs with 11 or more claims each, at $496,111 in total drug cost. In 2023, CMS named 8,206 claims across 131 drugs.
Dr. Williams' Part D claims by kind of drug, 2024
- Generic8,171 claims89%
- Brand-name942 claims10%
- Other22 claims0%
Dr. Williams' most prescribed drugs by claims, 2024
CMS names a drug when it has 11 or more claims. Share is of the claims for drugs CMS names.
Drug classes CMS tracks in Dr. Williams' Part D claims, 2024
- Opioids3%231 of 9,135 claims
- Antibiotics2%143 of 9,135 claims
Share of all Part D claims for each drug class CMS reports on. Classes with no claims are left out.
Part D claims for drugs CMS names, 2023 to 2024
- 2023
- 2024
- Claims for drugs CMS names
- 2023: 8,2062024: 8,4803%
Drugs named by CMS: 123 in 2024, 131 in 2023.
Sources: Medicare Part D Prescribers - by Provider and Drug (CMS), 2024 data, released May 6, 2026; and Medicare Part D Prescribers - by Provider (CMS), 2024 data
Dr. Elizabeth Hart Mahon Williams offers telehealth to Medicare patients
Dr. Williams accepts Medicare assignment, so Medicare's approved amount is taken as full payment. CMS lists Dr. Williams as offering telehealth.
- Accepts Medicare assignment
- Yes
- Offers telehealth
- Yes
Source: Doctors and Clinicians National Downloadable File (CMS)
For MedTech and pharma teams
Filter 7.4M+ HCPs by Medicare procedures, Part D drugs and Open Payments history, then reach them with verified contacts in one login.
Dr. Elizabeth Hart Mahon Williams has 3 publications on record
Dmand AI links 3 papers to Dr. Williams, published from 2021 to 2022.
Recent publications by Dr. Williams
Dev Cogn Neurosci
See who Dr. Williams researches with
Physician Network Discovery turns co-authorship, shared hospitals and shared groups into a map of who Dr. Williams works with, so you can find a warm path to the right internists.
Sources: PubMed (National Library of Medicine); and Dmand AI Research Linkage
Dr. Elizabeth Hart Mahon Williams received $10,620 in industry payments from 2016 to 2025
CMS Open Payments shows 617 general payments to Dr. Williams from 52 drug and device companies from 2016 to 2025. Food and beverage make up the largest share, 94% of the total. Abbvie Inc. paid the most, $1,269.
General payments to Dr. Williams by program year, 2016 to 2025
General payments to Dr. Williams by kind, 2016 to 2025
- Food and beverage$10,00294%
- Travel and lodging$5946%
- Education$240%
Companies that paid Dr. Williams the most, 2016 to 2025
Share is of all general payments to this clinician.
Source: Open Payments (CMS), 2025 data, released July 7, 2026
Dr. Elizabeth Hart Mahon Williams graduated from University of Missouri, Columbia School of Medicine
Dr. Williams graduated from University of Missouri, Columbia School of Medicine in 2011.
- Medical school
Source: Dmand AI Professional Profile Data
Sources for Dr. Elizabeth Hart Mahon Williams's profile data
| Data on this page | Source |
|---|---|
| NPI, name, sex, specialty and licenses | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Professional Profile Data |
| Practice locations and phone | Dmand AI Affiliation Data |
| Primary practice, affiliations and health system | Dmand AI Affiliation DataDmand AI Org Hierarchy Data |
| Medicare services and procedure codes | Medicare Physician & Other Practitioners - by Provider and Service (CMS) (opens in a new tab) |
| State medians for the same specialty | Dmand AI Peer Benchmarks |
| Medicare patients and the all-payer patient panel | Dmand AI Patient Panel DataMedicare Physician & Other Practitioners - by Provider (CMS) (opens in a new tab) |
| Part D prescribing | Medicare Part D Prescribers - by Provider and Drug (CMS) (opens in a new tab)Medicare Part D Prescribers - by Provider (CMS) (opens in a new tab) |
| MIPS scores, telehealth, assignment and procedure percentiles | Doctors and Clinicians National Downloadable File (CMS) (opens in a new tab) |
| Publications, topics and co-authors | PubMed (National Library of Medicine) (opens in a new tab)Dmand AI Research Linkage |
| Industry payments | Open Payments (CMS) (opens in a new tab) |
| Training, board certification and memberships | Dmand AI Professional Profile Data |
| EHR at each practice site | Dmand AI Technology Install Data |
| Similar physicians | Dmand AI Affiliation Data |
Data last refreshed October 2026Report an inaccuracyRemove my information
FAQ
Frequently asked questions about Dr. Elizabeth Hart Mahon Williams
Spotted something out of date? Email hello@dmand.ai and we will check the record. Contact details live in the free trial.
What is Dr. Elizabeth Hart Mahon Williams' NPI number?
Dr. Elizabeth Hart Mahon Williams' NPI number is 1952697468. It was assigned on June 22, 2011, and it is active in the NPI Registry.
What kind of doctor is Dr. Elizabeth Hart Mahon Williams?
Dr. Elizabeth Hart Mahon Williams is an internist in Saint Louis, Missouri. The primary specialty in the NPI Registry is Internal Medicine Physician (taxonomy code 207R00000X).
Where does Dr. Elizabeth Hart Mahon Williams practice?
Dr. Williams practices at 615 New Ballas Road, Saint Louis, MO 63141. Dr. Williams' primary practice is Mercy Hospital St. Louis in Saint Louis, Missouri, part of Mercy. Dmand AI also links Dr. Williams to 3 hospitals, 1 home health agency, 1 therapy and rehab clinic and 1 medical group.
What is Dr. Elizabeth Hart Mahon Williams' office phone number?
The practice phone on file for Dr. Williams is (314) 251-6000.
What is Dr. Elizabeth Hart Mahon Williams' medical license number?
Dr. Williams holds Missouri license 2011014989.
Which hospitals is Dr. Elizabeth Hart Mahon Williams affiliated with?
Dr. Williams practices at Mercy Hospital St. Louis in Saint Louis, Missouri. Dr. Williams is also affiliated with Missouri Baptist Medical Center. Dmand AI links Dr. Williams to 3 more hospitals.
What medical group is Dr. Elizabeth Hart Mahon Williams part of?
Dr. Williams is linked to Mercy Clinic East Communities. Dmand AI links Dr. Williams to 1 more medical group.
Does Dr. Elizabeth Hart Mahon Williams accept Medicare?
Yes. CMS data shows Dr. Williams billed Medicare for 1,236 services in 2024, and Dr. Williams accepts Medicare assignment.
Does Dr. Elizabeth Hart Mahon Williams offer telehealth?
Yes. The CMS Doctors and Clinicians file lists Dr. Williams as offering telehealth services.
How many Medicare patients does Dr. Elizabeth Hart Mahon Williams see?
CMS counts 322 Medicare patients who saw Dr. Williams in 2024, with an average age of 74.
Show 6 more questionsShow fewer questions
What services does Dr. Elizabeth Hart Mahon Williams bill to Medicare?
In 2024, Dr. Williams' most billed Medicare services were office visit, established patient (99214), medicare service (G0439) and medicare service (G2211).
Where did Dr. Elizabeth Hart Mahon Williams go to medical school?
Dr. Williams graduated from University of Missouri, Columbia School of Medicine in 2011.
What drugs does Dr. Elizabeth Hart Mahon Williams prescribe most?
In 2024 Medicare Part D data, Dr. Williams' most prescribed drugs by claims were Atorvastatin Calcium, Levothyroxine Sodium and Amlodipine Besylate.
Has Dr. Elizabeth Hart Mahon Williams received payments from drug or device companies?
CMS Open Payments shows $10,620 in general payments to Dr. Williams from 52 companies from 2016 to 2025. The largest total came from Abbvie Inc.
How long has Dr. Elizabeth Hart Mahon Williams been practicing?
Dr. Williams graduated from medical school in 2011, 15 years ago.
Does Dr. Elizabeth Hart Mahon Williams do research?
Dmand AI links 3 publications to Dr. Williams, published from 2021 to 2022.
Selling to internal medicine practices?
See internists in Missouri by site of care and group
Find the practices, groups and hospitals they work with, and the right people to contact at each.
- 30 days free
- Self-serve
- No credit card