Mary Katharine Lytwyn, MD
Emergency Medicine Physician · Houston, TX
Mary Katharine Lytwyn, MD is an emergency medicine physician with a practice address in Houston, Texas, and NPI 1336433440, issued on Jun 6, 2011. Check the license (Texas P9132, as entered in NPPES) on the Texas Medical Board; the Medicare figures below come from public CMS files.
- Name
- Mary Katharine Lytwyn
- Credential
- MD
- Primary taxonomy
- Emergency Medicine Physician 207P00000X
- License numbers
- P9132 TX
173193 NC
Self-reported in NPPES; status is on the state search - Practice location
- 20171 Chasewood Park Dr, Houston, TX 77070
- Phone
- (832) 534-6100
- Enumerated
- Jun 6, 2011
- Record last updated
- Mar 17, 2018 (not updated in 8 years: call before relying on the address or phone)
- Entity
- Type 1 · individual
8 nearest emergency medicine physician records → All 4,885 in Texas → Look up another NPI →
Also registered at 20171 Chasewood Park Dr
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Sai Padmaja Achanta, P.A.Physician Assistant1720096498
- Homaira Ahmed, M.DHospitalist Physician1609139369
- Jiten Bhula, MDHospitalist Physician1457771081
- Jeffrey Brady, CRNACertified Registered Nurse Anesthetist1922411081
- Amy Ciborowski, M.D.Internal Medicine Physician1669489704
- Bethany Culver, CRNACertified Registered Nurse Anesthetist1033407374
Verify Mary Katharine Lytwyn in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersTexas Medical Board
Search for license P9132Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
20% more Medicare Part D claims than the average emergency medicine physician in 2024
272 Medicare Part D claims for 152 beneficiaries, against an average of 226 among the 54,106 providers of this specialty who prescribed in Part D. Brand-name drugs were 6% of claims. 53 claims were for opioids.
Most prescribed
- Ondansetron Odt36 claims
- Hydrocodone-Acetaminophen29 claims
- Cefuroxime17 claims
- Dicyclomine Hcl13 claims
- Tramadol Hcl13 claims
- Prednisone12 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.
Mary Katharine Lytwyn among 4,885 emergency medicine physician records in Texas
Mary Katharine Lytwyn, MD is one of 4,885 emergency medicine physician records with a practice address in Texas. 83% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2011, is newer than 52% of them.
- NPI issued2011 · 52% of these records are older, 45% newer
- In a Medicare fileYes · 83% of these records are
- In the CMS Doctors and Clinicians fileNo · 57% of these records are
- Record last updated2018 · 55% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207P00000X and a Texas practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
818 emergency medicine physician records list a practice address in Houston
They are 818 of the 61,221 NPPES records with a practice address in Houston, and 4,885 emergency medicine physician records in Texas.
All 4,885 in Texas → Every provider in Houston → Emergency Medicine Physician nationwide →
The 8 emergency medicine physician records with the nearest ZIP codes
- Anthony Fasanella, D.O.Houston, TX 770701649384322
- Gregory Hall, D.O.Houston, TX 770701972617660
- Douglas Harrison, D.O.Houston, TX 770701720192420
- Lindsey Jackson, MD, PHDHouston, TX 770701013111681
- Patricia Klap, M.D.Houston, TX 770701841276656
- Christopher Langford, M.D.Houston, TX 770701164536884
- Yogita Mantena, DOHouston, TX 770701659358794
- Daniel Mao, M.D.Houston, TX 770701497843627
Common questions
What is Mary Katharine Lytwyn, MD's NPI number?
Mary Katharine Lytwyn, MD's National Provider Identifier (NPI) is 1336433440, issued on Jun 6, 2011. An NPI identifies a provider in billing; it is not a license.
Where is Mary Katharine Lytwyn, MD located?
The NPPES record lists a practice address at 20171 Chasewood Park Dr, Houston, TX, 77070. Phone: (832) 534-6100. Providers update this record themselves, so call before visiting.
How can I verify Mary Katharine Lytwyn, MD's license?
NPPES lists Texas license number P9132, as entered by the provider. Search the Texas Medical Board at https://profile.tmb.state.tx.us/Search.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Mary Katharine Lytwyn, MD prescribe under Medicare Part D?
In 2024, Mary Katharine Lytwyn, MD had 272 Medicare Part D claims for 152 beneficiaries; the average among emergency medicine physician prescribers was 226. 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.