J. XAVIER CASTILLO, MD appears in the CMS NPPES registry as a Public Health & General Preventive Medicine Physician provider holding MD credentials at 1111 AUGUSTA DR, HOUSTON, TX, 77057, with a listed phone of (713) 442-2400. NPI 1720013501 was issued on 07/11/2006. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what CASTILLO 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 5,101 prescription claims written by this provider, covering 478 Medicare beneficiaries and totaling roughly $333K in drug spend, split 9% brand-name and 91% generic by claim count, with an opioid prescribing rate of 2.3%. 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.

Public Health & General Preventive Medicine Physician is a narrow specialty nationwide, with 1,764 enrolled providers across 52 states and an average of 968 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.