Dr. Damon Matthew Armstrong, DO

Dr. Armstrong practices at Saint Francis Hospital Muskogee in Muskogee, Oklahoma, part of Saint Francis Health System.

Dr. Armstrong's NPI, 1548400500, was assigned on March 3, 2009. Dr. Armstrong holds Oklahoma license 5058.

Dr. Armstrong's primary practice is Saint Francis Hospital Muskogee, at 300 Rockefeller Drive, Muskogee, OK 74401 in Muskogee County. The practice phone is (918) 682-5501.

Dr. Armstrong's primary practice is Saint Francis Hospital Muskogee in Muskogee, Oklahoma, part of Saint Francis Health System. Dr. Armstrong is also affiliated with Saint Francis Hospital. The medical group on file is Warren Clinic. Dmand AI also links Dr. Armstrong to 5 more medical groups, 2 group practices and clinics and 1 clinical lab, each named with a free account.

Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Armstrong practices, 5 sites in all. Vendor and product names are available with a free account.

Surgery is Dr. Armstrong's primary specialty in the NPI Registry, under taxonomy code 208600000X. Dmand AI has Dr. Armstrong's licenses on file in 2 states: Oklahoma and California.

CMS data shows 76 Medicare services from Dr. Armstrong across 5 procedure codes in 2024, for 101 Medicare patients. Medicare paid $7,010 for them.

CMS counts 101 Medicare patients who saw Dr. Armstrong in 2026. The largest group is 65 to 74, with 44 patients. 75% of them have high blood pressure, and 75% have high cholesterol. 34% are also on Medicaid. Their average risk score is 2.06, where 1.00 is the Medicare average, so they are sicker than most Medicare patients.

Across all payers, Dmand AI patient panel data puts Dr. Armstrong's median patient age at 64, with 52% women.

In 2026, Dr. Armstrong wrote 113 Medicare Part D claims for 44 patients. 87% of them were for generic drugs. CMS names the drug for 76 of them, across 4 drugs with 11 or more claims each, at $329 in total drug cost. In 2023, CMS named 114 claims across 4 drugs.

Dr. Armstrong accepts Medicare assignment, so Medicare's approved amount is taken as full payment. CMS counts 27 procedures of upper gastrointestinal (gi) endoscopy for acid reflux by Dr. Armstrong, more than 54% of the clinicians it reports for that procedure.

Hernia repair (minimally invasive): 1 to 10 procedures (CMS shows small counts as a range)

Melanoma (skin cancer) excision: 1 to 10 procedures (CMS shows small counts as a range)

Removal of tissue: 1 to 10 procedures (CMS shows small counts as a range)

CMS Open Payments shows 19 general payments to Dr. Armstrong from 7 drug and device companies from 2019 to 2025. Education make up the largest share, 93% of the total. Intuitive Surgical, Inc. paid the most, $6,768.