National Health Insurance Act Article 53

No insurance benefits shall be paid by the Insurer for any one of the following events:1. Excessive hospitalization after being notified of discharge from the hospital but refused to do so;2. Expenses incurred from inappropriate repetitive medical visits or other improper use of medical resources; undergo treatment in contracted medical care institutions not designated by the Insurer. This restriction does not apply in medical emergencies;3. Treatment and drugs that are not medically necessary according to the pre-examination;4. Violating relevant medical procedures of this Insurance.
中文原文 全民健康保險法第53條
保險人就下列事項,不予保險給付:
一、住院治療經診斷並通知出院,而繼續住院之部分。
二、有不當重複就醫或其他不當使用醫療資源之保險對象,未依保險人輔導於指定之保險醫事服務機構就醫。
但情況緊急時不在此限。
三、使用經事前審查,非屬醫療必要之診療服務或藥物。
四、違反本保險規定之有關就醫程序。

English translation for reference only; the Chinese text prevails. Not legal advice.