ELIZABETH O'NEILL, MS ARNP-BC appears in the CMS NPPES registry as a Nurse Practitioner provider holding MS ARNP-BC credentials at 1000 E 23RD ST, SIOUX FALLS, SD, 57105, with a listed phone of (605) 322-7334. NPI 1215135348 was issued on 07/10/2007. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what O'NEILL most recently submitted to CMS rather than a vetted directory listing, which is why patients should always confirm the practice is still at this location before scheduling.

Medicare Part D records for calendar year 2023 show 185 prescription claims written by this provider, covering 41 Medicare beneficiaries and totaling roughly $56K in drug spend, split 17% brand-name and 83% generic by claim count, with an opioid prescribing rate of 14.1%. These figures capture only Medicare Part D — commercial insurance, Medicaid, and cash-pay prescriptions are not included, and any drug-beneficiary cell under 11 is suppressed by CMS for patient privacy.

Nurse Practitioner is a high-volume specialty nationwide, with 87,227 enrolled providers across 56 states and an average of 1,084 Part D claims per prescriber, so the context for interpreting these metrics differs meaningfully from a primary-care baseline. Important: PlainDoctor is a directory of publicly available government data, not medical advice, a malpractice database, or a quality rating. Inclusion here does not imply a recommendation, and absence of complaints or sanctions on this page does not mean none exist — always verify credentials through the NPPES NPI Registry, your state medical board, and the ABMS or AOA before making healthcare decisions.