NPPES file of Aug 9, 2026

Doctors and health care providers in O Fallon, MO

1,225 individual NPPES records list a practice address in O Fallon, 16th of 317 Missouri cities. The largest group is physical therapist: 131, 11% of the city's records, against 4% across Missouri. Page 6 of 25.

CMS NPPES registry, file of Aug 9, 2026 · method · Verify with CMS →

The 8 largest groups in O Fallon

Source: CMS NPPES primary taxonomy, file of Aug 9, 2026.

O Fallon in Missouri

  • Rank in Missouri16th of 317 cities by records
  • Share of the state1.1% of Missouri's records
  • Specialties present25 or more taxonomy codes
  • Top three groups27.3% of all records
  • Physical Therapist rank3rd of the 10 Missouri cities with the most

Compared with Missouri as a whole, O Fallon has 6.3× the state's share of orthodontics and dentofacial orthopedics dentistry records and 0.59× its share of internal medicine physician records.

Providers in O Fallon, alphabetically

  1. Katherine Derickson, PHARM.D.Pharmacist1558702050
  2. Mrinali DeshpandePhysical Therapist1811727449
  3. Sunita Dharmavarapu, MDAnesthesiology Physician1063542793
  4. Lindsay Dickerhoff, M.D.Obstetrics & Gynecology Physician1790028520
  5. Samantha Diehl, D.C.Chiropractor1275871592
  6. Erin Diepenbrock, RPHPharmacist1659654739
  7. Emil Difilippo, M.D.Orthopaedic Surgery Physician1205839354
  8. Kenneth Dildine, ATC, LATAthletic Trainer1952880023
  9. Bridget Dimercurio, OTR/LPediatric Occupational Therapist1528467776
  10. Ralph Dinges, DMDDentist1003428335
  11. McKayla Dinwiddie, MDFamily Medicine Physician1194429290
  12. Dylan Dix, DCChiropractor1134831969
  13. Tuyet Doan, O.D.Optometrist1578569653
  14. Amanda Dobbs, M.H.S., CCC-SLPSpeech-Language Pathologist1194278994
  15. Colin Dolan, MDPediatrics Physician1629700794
  16. Mark Dolson, DDS,PCGeneral Practice Dentistry1013054170
  17. Carly Donahue, PT, DPTPhysical Therapist1487308789
  18. Rosemary Doss, D.P.T.Physical Therapist1316138365
  19. Jeff Dougherty, D.M.DGeneral Practice Dentistry1598828030
  20. Carla Douglas, OTRLOccupational Therapist1194867754
  21. Rachel DovePharmacist1215540125
  22. Katherine Dowell, PA-CPhysician Assistant1497501480
  23. Marissa Drake, RBTBehavior Technician1811770985
  24. Emily Drummer, PTAPhysical Therapy Assistant1154667020
  25. Jennifer Dubbert, PTPhysical Therapist1912409269
  26. Drew Dudek, DPT, ATCPhysical Therapist1427530724
  27. Sandra Dufrenne, RNRegistered Nurse1730411174
  28. Keri Dunivan, OT/LOccupational Therapist1073794525
  29. Loretta Dunkmann, M.S.Speech-Language Pathologist1023481314
  30. Carrie Dunning, LPCProfessional Counselor1730420084
  31. Molly Dunsworth, MA CCC/SLPSpeech-Language Pathologist1255910311
  32. Joan Durbin, RPTPhysical Therapist1548582604
  33. Ashley DyerSpeech-Language Pathologist1699055103
  34. Christy Dyer, FNP-BCFamily Nurse Practitioner1184895690
  35. Elizabeth Eaton, MSW, LCSWClinical Social Worker1194881870
  36. Adrienne Ebersole, DPTPhysical Therapist1750909784
  37. Tina Ebert, CCC-SLPSpeech-Language Pathologist1215169743
  38. Gloria Michelle Edacheril, NPFamily Nurse Practitioner1144502253
  39. Dennis Edson, RPHPharmacist1801179569
  40. Sarah Effler, PT, MPTPhysical Therapist1639517857
  41. Andrew Eilers, DPTPhysical Therapist1073298162
  42. Anna Eise, RN, BSNRegistered Nurse1235086448
  43. Diana Eisenbath, RNFARegistered Nurse First Assistant1700278421
  44. Ashley Ekiss, DPTPhysical Therapist1760622310
  45. Dora EllegoodPharmacist1255935474
  46. Aleasha Elliott, APRN, NP-CFamily Nurse Practitioner1639583222
  47. Mary Ellison, RPHPharmacist1871876953
  48. Sue EllisonCounselor1710237607
  49. Gina Elmendorf, OTR/LPediatric Occupational Therapist1588008353
  50. Taylor Elmore, PT, DPTPhysical Therapist1053083840

The largest Missouri cities

  1. Saint Louis27,605
  2. Kansas City13,759
  3. Springfield6,403
  4. Columbia6,004
  5. Joplin2,443

All of Missouri →

How to read this directory

O Fallon, Missouri appears in the CMS National Plan and Provider Enumeration System with 1,225 registered healthcare providers spanning 25 or more distinct NUCC-taxonomy specialties. This count includes every individual clinician who has applied for an NPI and listed a practice address in O Fallon - physicians, dentists, nurse practitioners, physician assistants, chiropractors, physical therapists, optometrists, psychologists, podiatrists, and every other credentialed provider type CMS tracks. It does not measure hospital beds, urgent-care capacity, or whether a given clinic is accepting new patients; it measures the pool of professionals with current NPI enrollment and a O Fallon practice location on file. Every figure is drawn from the federal National Provider Identifier Registry (CMS NPPES) - more than 7 million providers, maintained since May 2007, with 2024 Medicare Part D data, and, according to CMS, can be searched, compared, and traced in our methodology.

The provider mix in O Fallon is weighted toward Physical Therapist (131 clinicians, followed by Speech-Language Pathologist with 119 and Pharmacist with 84). That distribution reflects how NPPES records specialty: providers self-select a primary taxonomy code, so a family physician who also practices geriatrics will show up under whichever NUCC code they registered first. Relative to Missouri's population, O Fallon reports roughly 19.8 providers per 100,000 residents using the state-level denominator, which is a rough proxy rather than a precise access-to-care measurement; the true catchment area of any {cityName} clinician extends beyond the municipal boundary.

Of Missouri's most common specialties, Behavior Technician is the most prominent one with no provider currently listing a O Fallon practice address, a coverage gap O Fallon patients typically fill by traveling to a larger nearby hub.

For O Fallon patients, this directory is most useful as a starting shortlist. Important: PlainDoctor is a directory of publicly available CMS government data, not a review site, a ranking, or medical advice. NPPES data is self-reported and refreshed monthly; call the practice directly to confirm the provider is still there, accepts your insurance, and is taking new patients.

For informational purposes only; this directory is not medical advice and not a substitute for checking a license. See also: how to find a doctor and how to verify one.

Common questions

How many doctors are in O Fallon, MO?

There are 1,225 registered healthcare providers in O Fallon, MO, covering 25 or more specialties. This includes physicians, dentists, therapists, and other licensed providers.

What are the most common medical specialties in O Fallon?

The most common specialties in O Fallon are Physical Therapist, Speech-Language Pathologist, Pharmacist, Professional Counselor, Chiropractor. Physical Therapist has the most providers with 131.

Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov). Records are self-reported registrations, not licenses.

Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.