Navacaprant (BTRX-335140) 是一种选择性、口服活性的 κ 阿片受体 (KOR) 拮抗剂，对 κOR、μOR 和 δOR 的 IC50 值分别为 0.8 nM、110 nM 和 6500 nM。

PZM21 is a potent and selective μ opioid receptor agonist with an EC50 of 1.8 nM.

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

LY2444296 is a short-acting kappa opioid receptor antagonist.

(R)-ZINC-3573 can activate endogenous MRGPRX2 in a human mast cell line and induce degranulation and calcium release.

Alvimopan is a peripherally acting mu-opioid receptor (PAM-OR, IC50= 1.7 nM) antagonist for accelerating gastrointestinal recovery after surgery.

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).

LY2940094 is a potent and selective nociceptin receptor antagonist which inhibits excessive feeding behavior in rodents.

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

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

(-)-Menthol is a natural product obtained from the oils of corn mint, peppermint, or other mints, as a weak kappa opioid receptor agonist. It has local anesthetic and counterirritant qualities, and used to relieve minor throat irritation.

Matrine (Matridin-15-one)存在于苦参属植物中，作为κ阿片受体和μ受体激动剂。它具有多种药理作用，包括抗癌、抗氧化应激、抗炎和抗凋亡作用。苦参碱在研究人类非小细胞肺癌、肝癌、乳头状甲状腺癌和急性肾损伤（AKI）等疾病中具有潜力。

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

Meptazinol HCl is both a partial agonist of μ1 opioid receptor and an AChE inhibitor.