Clonitazene is a synthetic opioid analgesic, structurally related to etonitazene. In the USA clonitazene is a schedule I narcotic controlled substance.

Clonitazene:
https://drugs.ncats.io/drug/S90R21A2V2

Clonitazene

Duration: An opioid that is roughly three times as potent as Morphine. Is related to Etonitazene, which is about 1000-1500x the potency of Morphine.
Route	Onset	Duration	After Effects
Tripsit Factsheets
Clonitazene Basic Information: http://drugs.tripsit.me/clonitazene
Oral:	10-30 minutes	4-8 hours	1-8 hours

Clonitazene is an opioid approximately three times the potency of morphine. It is related to etonitazene, an opioid of about 60 times the potency of morphine. Clonitazene is not currently marketed