Doctor profile · Federal record

Dr. Thoo Tan, DO

Obstetrics & Gynecology Physician (CMS: Obstetrics/Gynecology) · Mason City, IA

  • NPI 1104857127
  • Accepts Medicare
  • 36 yrs in practice
  • Male
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
1010 4Th St Sw, Suite 220
Mason City, IA 504012857
(641) 428-5100
fax (641) 428-5115

Credentials & registration

NPPES · NUCC
NPI registered
July 2006 — 20 yrs on file
Profile last updated
July 14, 2025
Year of graduation
1990 — 36 yrs since
Specialty taxonomy
207V00000X — NUCC code
State license (1)
Iowa #02918

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1104857127. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
70
Distinct HCPCS
3
Medicare allowed
$4,158
HCPCS Description Services Patients Avg allowed
99213 Established patient office or other outpatient visit, 20-29 minutes 31 20 $62
99203 New patient office or other outpatient visit, 30-44 minutes 22 22 $77
99212 Established patient office or other outpatient visit, 10-19 minutes 17 16 $33

In context: peer comparison

Among 6 peers in Mason City Obstetrics & Gynecology Physician, average services per provider: 25. This provider delivers 2.8× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$31
Transactions
1
Manufacturers
1
Payer (manufacturer) Industry Txns Amount
Intuitive Surgical, INC. 1 $31.44

By nature of payment

Food and Beverage
$31

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
47
Patients
0
Total drug cost
$1,147
Drug Type Claims Patients Total cost
Estradiol Generic 29 0 $800
Oxybutynin Chloride ER (Oxybutynin Chloride) Brand 18 0 $347

Frequently asked questions

Auto-generated from federal data
What is Dr. Thoo Tan's medical specialty?
Dr. Thoo Tan practices Obstetrics & Gynecology Physician in Mason City, IA.
Where does Dr. Thoo Tan practice?
Dr. Thoo Tan practices at 1010 4Th St Sw, Mason City, IA 504012857. Office phone: 6414285100.
What is Dr. Thoo Tan's NPI?
Dr. Thoo Tan's National Provider Identifier (NPI) is 1104857127, issued by NPPES.
Does Dr. Thoo Tan accept Medicare assignment?
Yes. Dr. Thoo Tan accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Thoo Tan commonly perform?
Top Medicare-reported procedures in 2023: Established patient office or other outpatient visit (HCPCS 99213); New patient office or other outpatient visit (HCPCS 99203); Established patient office or other outpatient visit (HCPCS 99212). Source: CMS Medicare Physician & Other Practitioners file.