William H. Mollohan, D.O.
Internal Medicine Physician · Naperville, IL
William H. Mollohan, D.O. is an internal medicine physician with a practice address in Naperville, Illinois, and NPI 1720006919, issued on Jul 17, 2006. Check the license on the Illinois Department of Financial and Professional Regulation; the Medicare figures below come from public CMS files.
- Name
- William H. Mollohan
- Credential
- D.O.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- Practice location
- 535 Fairway Dr, Naperville, IL 60563
- Phone
- (630) 548-5936
- Enumerated
- Jul 17, 2006
- Record last updated
- Jul 9, 2007 (not updated in 19 years: call before relying on the address or phone)
- Fax
- (630) 548-5940
- Medicaid ID
- 200236 IL
- Medicare enrollment
- Enrolled (PECOS I20040512001121); accepts Medicare assignment
- Medical or professional school
- Oklahoma State University College Of Osteopathic Medicine, 1985
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 7,238 in Illinois → Look up another NPI →
Also registered at 535 Fairway Dr
A shared address usually means a shared clinic or building; it does not show who employs whom.
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Verify William H. Mollohan in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersIllinois Department of Financial and Professional RegulationCheck the board
- 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
71% fewer Medicare Part D claims than the average internal medicine physician in 2024
923 Medicare Part D claims for 120 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 14% of claims. 29 claims were for opioids.
Most prescribed
- Amlodipine Besylate32 claims
- Atorvastatin Calcium29 claims
- Diclofenac Sodium27 claims
- Gabapentin26 claims
- Furosemide23 claims
- Eliquis20 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
Industry payments in 2024: $95.25
1 payment: food and beverage; the largest payer was Organogenesis Inc. The 50,334 providers of this specialty with any payment received $1,303.06 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
Bills Medicare through one group practice
- Beyond Wound Care IncSchaumburg, IL
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
William H. Mollohan among 7,238 internal medicine physician records in Illinois
William H. Mollohan, D.O. is one of 7,238 internal medicine physician records with a practice address in Illinois. 73% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2006, is newer than 7% of them.
- NPI issued2006 · 7% of these records are older, 61% newer
- In a Medicare fileYes · 73% of these records are
- In the CMS Doctors and Clinicians fileYes · 50% of these records are
- Graduated1985 · median 2003 among the 3,580 with a school on file
- Record last updated2007 · 47% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a Illinois practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
75 internal medicine physician records list a practice address in Naperville
They are 75 of the 4,634 NPPES records with a practice address in Naperville, and 7,238 internal medicine physician records in Illinois.
All 7,238 in Illinois → Every provider in Naperville → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Rohini Bhat, MDNaperville, IL 605631700988706
- Mary Dea, DONaperville, IL 605631518951474
- Barbara Emery-Stolzer, MDNaperville, IL 605631982698841
- Peter Furey, M.D.Naperville, IL 605631609859289
- Cicily Jones, MDNaperville, IL 605631255396511
- Mary King, MDNaperville, IL 605631649246729
- Francine Long, MDNaperville, IL 605631063406924
- Katherine Pickett, MDNaperville, IL 605631740258581
Common questions
What is William H. Mollohan, D.O.'s NPI number?
William H. Mollohan, D.O.'s National Provider Identifier (NPI) is 1720006919, issued on Jul 17, 2006. An NPI identifies a provider in billing; it is not a license.
Where is William H. Mollohan, D.O. located?
The NPPES record lists a practice address at 535 Fairway Dr, Naperville, IL, 60563. Phone: (630) 548-5936. Providers update this record themselves, so call before visiting.
How can I verify William H. Mollohan, D.O.'s license?
Search the Illinois Department of Financial and Professional Regulation at https://idfpr.illinois.gov/checklicense.html. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does William H. Mollohan, D.O. prescribe under Medicare Part D?
In 2024, William H. Mollohan, D.O. had 923 Medicare Part D claims for 120 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
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.