JOHN CONSTANTAKIS, DO appears in the CMS NPPES registry as a Neurology Physician provider holding DO credentials at 800 UNIVERSITY BAY DR STE 300, MADISON, WI, 53705, with a listed phone of (608) 264-3093. NPI 1669051405 was issued on 04/07/2021. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what CONSTANTAKIS 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 65 prescription claims written by this provider, covering 32 Medicare beneficiaries and totaling roughly $7K 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.

Neurology Physician is a mid-sized specialty nationwide, with 19,866 enrolled providers across 54 states and an average of 1,309 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.