A physician or dentist engaged in medical treatment covered by health insurance at a medical institution providing services covered by health insurance or a pharmacist engaged in prescription covered by health insurance at a pharmacy providing services covered by health insurance must be a physician or dentist registered by the Minister of Health, Labour and Welfare (hereinafter collectively referred to as a "physician providing health insurance treatment") or a pharmacist registered by the Minister (hereinafter referred to as a "pharmacist filling health insurance prescriptions").