Systematic (IUPAC) name
2-(3,4-dichlorophenyl)- N-methyl- N-[(5R,7S,8S)- 7-pyrrolidin-1-yl- 1-oxaspiro[4.5]decan-8-yl] acetamide
Clinical data
Legal status
Routes N/A
CAS number  YesY
ATC code None
IUPHAR ligand
Chemical data
Formula C22H30Cl2N2O2 
Mol. mass 425.392 g/mol

Spiradoline (U-62066) is a drug which acts as a highly selective κ-opioid agonist.[1] It has analgesic,[2] diuretic[3] and antitussive effects,[4] and produces subjective effects in animals similar to those of ketocyclazocine and allylnormetazocine.[5] The main effect in humans is sedation, along with analgesic and diuretic effects, but significant side effects such as dysphoria and hallucinations have stopped it from being used clinically.[6] Kappa-agonists have been shown to react negatively with the mu receptor, instead of having an assumed synergy since they are both opioid receptors, such as with the mu (μ) receptors and delta (δ) receptors (which both mediate pain-relief, euphoria and overall potency of opioid effects).

See also


  1. ^ Vonvoigtlander PF, Lewis RA. Analgesic and mechanistic evaluation of spiradoline, a potent kappa opioid. Journal of Pharmacology and Experimental Therapeutics. 1988 Jul;246(1):259-62. PMID 2839665
  2. ^ Kunihara M, Ohyama M, Nakano M, Hayashi S. Analgesic activity of spiradoline mesylate (U-62,066E), a kappa opioid agonist in mice. Life Sciences. 1989;45(13):1191-8. PMID 2796604
  3. ^ Yamada K, Imai M, Yoshida S. Mechanism of diuretic action of U-62,066E, a kappa opioid receptor agonist. European Journal of Pharmacology. 1989 Jan 31;160(2):229-37. doi:10.1016/0014-2999(89)90495-0 PMID 2547626
  4. ^ Kamei J, Tanihara H, Kasuya Y. Antitussive effects of two specific kappa-opioid agonists, U-50,488H and U-62,066E, in rats. European Journal of Pharmacology. 1990 Oct 9;187(2):281-6. PMID 2272363
  5. ^ Holtzman SG. Further characterization of the discriminative stimulus effects of spiradoline. Pharmacology, Biochemistry and Behaviour. 2000 Jul;66(3):517-22. PMID 10899364
  6. ^ Wadenberg ML. A review of the properties of spiradoline: a potent and selective kappa-opioid receptor agonist. CNS Drug Reviews. 2003 Summer;9(2):187-98. PMID 12847558