AR-M 1000390 hydrochloride (the hydrochloric acid of ARM-390; AR-M1000390) is a potent, highly selective agonist of δ opioid receptor that can induce insulin depletion in the rat and RINm5F cells.

PZM21 is a novel, potent and selective Gi activator with exceptional selectivity for μ opioid receptor (μOR) and minimal β-arrestin-2 recruitment with an EC50 of 1.8 nM.

Trimebutine (Mebutin; Debridat; Polibutin; Modulon; Dromostat; Ibutin; Polibutin; TM 906; Trimedat) is a potent agonist of peripheral mu, kappa and delta (μ, κ, and δ) opioid receptors.

DAMGO is a novel, potent and selective μ-opioid receptor agonist with a Kd of 3.46 nM for native μ-OPR.

Nitrendipine (BAY-E5009; BAY E-5009; Bayotensin; Bayotensin, Baypress, Nidrel, Deiten) is a potent dihydropyridine (DHP) calcium channel blocker (CCB) with antihypertensive effects.

Difelikefalin (MR-13A9; CR-845; MR-13A-9; trade name Korsuva) is a novel, peripherally specific, and potent kappa opioid receptor agonist approved in 2021 as an analgesic opiod peptide for the treatment of moderate-to-severe itching.

Loperamide HCl (R18553; ADL-2-1294; R-18553; ADL 2-1294; Imodium; Dissenten; Fortasec), the hydrochloride salt of loperamide, is a potent and selective μ-opioid receptor agonist used to reduce the frequency of diarrhea, also for IBD-inflammatory bowel disease and short bowel syndrome.

Meptazinol (IL-22811; WY-22811; IL22811; WY22811; trade name Meptid), the hydrochloride salt of meptazinol, is a centrally actiing opioid analgesic, which inhibits [3H]dihydromorphine binding with IC50 of 58 nM.

ADL5859 HCl (ADL 5859; ADL-5859), the hydrochloride salt of ADL5859, is a potent, orally bioavailable δ-opioid receptor agonist with important biological activity.

Methylnaltrexone bromide is a novel and potent μ-opioid antagonist.