BTRX-335140 is a potent and selective KOR antagonist with IC50 (KOR)=0.8 nM.

[Leu5]-Enkephalin, an endogenous opioid neurotransmitter or neuromodulator, is an agonist of µ and δ opioid receptors.

Bevenopran is a peripheral μ-opioid receptor antagonist.

Alvimopan is a peripherally selective opioid mu receptor antagonist.

Nociceptin, a 17 amino acid neuropeptide, is endogenous ligand for the opioid-like G-protein coupled receptor, ORL1 (opioid receptor-like 1).

LY-2456302 is a potent and centrally-penetrant kappa opioid receptor antagonist with a Ki of 0.807 nM.

Difelikefalin (CR-845; FE-202845) is a peripherally restricted and selective agonist of kappa opioid receptor (KOR). Difelikefalin produces anti-inflammatory effects and has the potential in modulating pruritus in conditions such as chronic kidney disease.

DAMGO is a highly selective peptide agonist for the μ opioid receptor.

Trimebutine Maleate is an agonist effect on peripheral μ, k and δ opiate receptors, and also shows antimuscarinic effect.

(+)-Matrine is a naturally occuring κ-opioid and μ-opioid receptor agonist.

Loperamide HCl is a potent and selective μ-opioid receptor agonist.

N-Desmethylclozapine is a dengue virus inhibitor, and an agonist of δ-opioid receptor.

Sec-O-glucosylhamaudol is one of the active ingredients isolated and purified from the herb of Ledebouriella seseloides.