| DB00318 | Codeine | approved, illicit | yes | agonist | Details |
| DB00327 | Hydromorphone | approved, illicit | yes | partial agonist | Details |
| DB00647 | Dextropropoxyphene | approved, illicit, investigational, withdrawn | yes | agonist | Details |
| DB00844 | Nalbuphine | approved | yes | antagonist | Details |
| DB00956 | Hydrocodone | approved, illicit, investigational | yes | agonist | Details |
| DB00295 | Morphine | approved, investigational | yes | agonist | Details |
| DB00611 | Butorphanol | approved, illicit, vet_approved | yes | agonist | Details |
| DB00813 | Fentanyl | approved, illicit, investigational, vet_approved | yes | agonist | Details |
| DB01183 | Naloxone | approved, vet_approved | yes | antagonist | Details |
| DB01497 | Etorphine | illicit, vet_approved | yes | agonist | Details |
| DB01548 | Diprenorphine | illicit, vet_approved | yes | antagonist | Details |
| DB01439 | 3-Methylthiofentanyl | experimental, illicit | yes | agonist | Details |
| DB01444 | Dimethylthiambutene | experimental, illicit | unknown | agonist | Details |
| DB00836 | Loperamide | approved | unknown | agonist | Details |
| DB00704 | Naltrexone | approved, investigational, vet_approved | yes | antagonist | Details |
| DB01571 | 3-Methylfentanyl | illicit | yes | agonist | Details |
| DB05050 | ADL5859 | investigational | unknown | | Details |
| DB00497 | Oxycodone | approved, illicit, investigational | yes | agonist | Details |
| DB06204 | Tapentadol | approved | unknown | agonist | Details |
| DB06409 | Morphine glucuronide | investigational | unknown | | Details |
| DB01452 | Diamorphine | approved, illicit, investigational | unknown | agonist | Details |
| DB00193 | Tramadol | approved, investigational | unknown | agonist | Details |
| DB00333 | Methadone | approved | yes | agonist | Details |
| DB00708 | Sufentanil | approved, investigational | unknown | agonist | Details |
| DB01535 | Carfentanil | illicit, investigational, vet_approved | yes | agonist | Details |
| DB01192 | Oxymorphone | approved, investigational, vet_approved | unknown | antagonist | Details |
| DB00321 | Amitriptyline | approved | unknown | agonist | Details |
| DB01081 | Diphenoxylate | approved, illicit | unknown | agonist | Details |
| DB00854 | Levorphanol | approved | unknown | agonist | Details |
| DB01565 | Dihydromorphine | experimental, illicit | unknown | agonist | Details |
| DB00921 | Buprenorphine | approved, illicit, investigational, vet_approved | unknown | antagonist | Details |
| DB06274 | Alvimopan | approved, investigational | unknown | antagonist | Details |
| DB00899 | Remifentanil | approved | unknown | agonist | Details |
| DB06738 | Ketobemidone | investigational | yes | agonist | Details |
| DB00514 | Dextromethorphan | approved | unknown | agonist | Details |
| DB01221 | Ketamine | approved, vet_approved | unknown | binder | Details |
| DB09272 | Eluxadoline | approved, investigational | yes | antagonist | Details |
| DB11691 | Naldemedine | approved, investigational | yes | antagonist | Details |
| DB06230 | Nalmefene | approved, investigational, withdrawn | yes | antagonist | Details |
| DB09061 | Cannabidiol | approved, investigational | unknown | | Details |
| DB09209 | Pholcodine | approved, illicit | unknown | antagonist | Details |
| DB11130 | Opium | approved, illicit | yes | agonist | Details |
| DB14011 | Nabiximols | investigational | unknown | | Details |
| DB14009 | Medical Cannabis | experimental, investigational | unknown | | Details |
| DB14146 | Loxicodegol | investigational | unknown | agonist | Details |
| DB09173 | Butyrfentanyl | illicit | unknown | agonist | Details |
| DB01238 | Aripiprazole | approved, investigational | unknown | ligand | Details |
| DB12668 | Metenkefalin | investigational | unknown | agonist | Details |
| DB06288 | Amisulpride | approved, investigational | no | agonist | Details |
| DB12543 | Samidorphan | approved, investigational | unknown | partial agonist | Details |