IPA: /ˌʌnˈmɛtəˌbɒlaɪzd/
KK: /ʌnˌmɛtəˈbɑːlaɪzd/
Not changed or processed by the body's metabolism.
The drug remained unmetabolized in the bloodstream for several hours.
Unmetabolized → It is formed from "un-" (meaning not) and "metabolized" (from Greek "metabole" meaning change). The word "unmetabolized" means not having undergone the process of change or transformation that occurs in metabolism.
Think of 'not' ('un-') having undergone a 'change' ('metabolized') — that's why unmetabolized refers to something that hasn't changed or transformed.