GREGORY BARNELL, NP appears in the CMS NPPES registry as a Adult Health Nurse Practitioner provider holding NP credentials at 275 W MACARTHUR BLVD, OAKLAND, CA, 94611, with a listed phone of (510) 752-1000. NPI 1083966931 was issued on 10/02/2012. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what BARNELL 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 24 prescription claims written by this provider, covering 18 Medicare beneficiaries and totaling roughly $629 in drug spend. 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.

Adult Health Nurse Practitioner is a mid-sized specialty nationwide, with 29,492 enrolled providers across 55 states and an average of 1,201 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.