 | |
 | |
| Clinical data | |
|---|---|
| Other names | Fenazocina, Phenazocinum, DEA No. 9715 |
| Routes of administration | Oral |
| ATC code | |
| Legal status | |
| Legal status | |
| Identifiers | |
| |
| CAS Number | |
| PubChemCID | |
| ChemSpider |
|
| UNII | |
| KEGG | |
| ChEMBL | |
| CompTox Dashboard(EPA) | |
| ECHA InfoCard | 100.004.397 |
| Chemical and physical data | |
| Formula | C22H27NO |
| Molar mass | 321.464 g·mol−1 |
| 3D model (JSmol) | |
| |
| |
 N Y (what is this?) (verify) | |
Phenazocine (brand namesPrinadol,Narphen) is anopioid analgesicdrug, which is related topentazocine and has a similar profile of effects.[2]
Effects of phenazocine include analgesia andeuphoria, also may includedysphoria andhallucinations at high doses, most likely due to action atκ-opioid andσ receptors.[3]Phenazocine appears to be a much stronger analgesic with fewer side effects than pentazocine, probably due to a more favorableμ/κ binding ratio. Phenazocine is a much more potent analgesic than pentazocine and other drugs in the benzomorphan series, most probably due to the presence of anN-phenethyl substitution, which is known to boost μ-opioid activity in many classes of opioid analgesics.[4] Also, it does not cause spasm of thesphincter of Oddi, making it more suitable than morphine for the treatment ofbiliary orpancreatic pain.[5]
Regarding the twoenantiomers of phenazocine, (R)-phenazocine[clarification needed] has twenty times the potency ofmorphine as an analgesic,[6] while (S)-phenazocine has about four times the potency of morphine.[7][full citation needed]
Phenazocine was invented in the 1950s.[8][9] It was one of a number ofbenzomorphan opioids (includingpentazocine,dezocine, andcyclazocine) developed in the search for non-addictive strong analgesics.
Phenazocine was once widely used, and was mainly supplied as 5 mg tablets of thehydrobromide salt for sublingual use (Narphen, Prinadol and other names), but its use was discontinued in theUnited Kingdom in 2001.[10]
Phenazocine was briefly used in the United States but fell out of favor;[citation needed] it remains a Schedule II substance under the Comprehensive Drug Abuse Control & Prevention Act (Controlled Substances Act) of 1970 (CSA) but is not manufactured. The DEA ACSCN for phenazocine is 9715 and its 2013 annual manufacturing quota was 6 grams.[11]