JOSEPH HSIOU, DDS appears in the CMS NPPES registry as a Periodontics provider holding DDS credentials at 2130 HUNTINGTON DR, SOUTH PASADENA, CA, 91030, with a listed phone of (626) 441-4511. NPI 1689813735 was issued on 02/12/2009. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what HSIOU 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 20 prescription claims written by this provider, covering 16 Medicare beneficiaries and totaling roughly $139 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.

Periodontics is a mid-sized specialty nationwide, with 6,061 enrolled providers across 53 states and an average of 264 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.