Etonitazene is a highly potent narcotic analgesic (1000–1500x morphine). It's the one of several benzimidazole opioids, and is structurally related to clonitazene (where the p-ethoxybenzyl group is replaced by a p-chlorobenzyl group. However, clonitazene itself has only 3x the potency of morphine.). It has a strong dependency potential similar to that of morphine and therefore is not used in humans. It is, however, useful in addiction studies on animals. It is the most potent benzimidazole opioid currently known. Other analogues of considerable potency are as follows: Methyl (10x morphine) Ethyl (30x morphine) Propyl (50x morphine) Methoxy (100x morphine) Isopropoxy (500x morphine) Butoxy (200x morphine) Methylthio (50x morphine) Ethylthio (30x morphine) These groups replace the p-ethoxy group - there are other possible modifications but these are the most significant. The drug has proved very important in mapping out the opiate receptor and some experimental compounds in which phenolic groupings have been replaced with nitro groupings have proved more active than the parent compound. Illicit production and sale of etonitazene has been limited. This compound was identified on the illegal drug market in Moscow in 1998, appeared to have been illicitly manufactured, and was primarily smoked. In another case a chemist at Morton Thiokol called Thomas K Highsmith produced the compound and placed it in a nasal inhaler. Such was the level of his addiction, insufficient amounts of methadone were given and he committed suicide before the case went to court