Fentanyl, also spelled fentanil, is a powerful opioid used as a pain medication and, together with other medications, for anesthesia. It is also used as a recreational drug, sometimes mixed with heroin, cocaine, or methamphetamine, and its potentially deadly overdose effects can be neutralized by naloxone. Fentanyl is commonly used to create counterfeit drugs marketed as OxyContin, Xanax, Adderall, and other pills. It has a rapid onset and its effects generally last under two hours. Medically, it is used by injection, nasal spray, or skin patch, or absorbed through the cheek as a lozenge or tablet.
Hydromorphone, also known as dihydromorphinone, and sold under the brand name Dilaudid among others, is an opioid used to treat moderate to severe pain. Typically, long-term use is only recommended for pain due to cancer. It may be used by mouth or by injection into a vein, muscle, or under the skin. Effects generally begin within half an hour and last for up to five hours.
Pethidine, also known as meperidine and sold under the brand name Demerol among others, is a synthetic opioid pain medication of the phenylpiperidine class. Synthesized in 1938 as a potential anticholinergic agent by the German chemist Otto Eisleb, its analgesic properties were first recognized by Otto Schaumann while working for IG Farben, Germany. Pethidine is the prototype of a large family of analgesics including the pethidine 4-phenylpiperidines, the prodines, bemidones and others more distant, including diphenoxylate and analogues.
Carfentanil or carfentanyl, sold under the brand name Wildnil, is an opioid analgesic which is used in veterinary medicine to anesthetize large animals such as elephants and bears. It is typically administered in this context by tranquilizer dart. Carfentanil has also been used in humans for imaging of opioid receptors. It has additionally been encountered as an illicit drug, typically used by injection, insufflation, or inhalation. Deaths have been reported in association with carfentanil.
Levorphanol is an opioid medication used to treat moderate to severe pain. It is one of two enantiomers of the compound racemorphan.
Ketobemidone, sold under the brand name Ketogan among others, is a powerful synthetic opioid painkiller. Its effectiveness against pain is in the same range as morphine, and it also has some NMDA-antagonist properties imparted, in part, by its metabolite norketobemidone. This may make it useful for some types of pain that do not respond well to other opioids. It is marketed in Denmark, Iceland, Norway and Sweden and is used for severe pain.
Hydroxypethidine (Bemidone) is an opioid analgesic that is an analogue of the more commonly used pethidine (meperidine). Hydroxypethidine is slightly more potent than meperidine as an analgesic, 1.5x meperidine in potency, and it also has NMDA antagonist properties like its close relative ketobemidone.
Dihydroetorphine was developed by K. W. Bentley at McFarlan-Smith in the 1960s and is a potent opioid analgesic used mainly in China. It is a derivative of the better-known opioid etorphine, a very potent veterinary painkiller and anesthetic medication used primarily for the sedation of large animals such as elephants, giraffes, and rhinos.
Nalorphine (INN), also known as N-allylnormorphine, is a mixed opioid agonist–antagonist with opioid antagonist and analgesic properties. It was introduced in 1954 and was used as an antidote to reverse opioid overdose and in a challenge test to determine opioid dependence.
Lofentanil is one of the most potent opioid analgesics known and is an analogue of fentanyl, which was developed in 1960. It is most similar to the highly potent opioid carfentanil (4-carbomethoxyfentanyl), only slightly more potent. Lofentanil can be described as 3-methylcarfentanil, or 3-methyl-4-carbomethoxyfentanyl. While 3-methylfentanyl is considerably more potent than fentanyl itself, lofentanil is only slightly stronger than carfentanil. This suggests that substitution at both the 3 and 4 positions of the piperidine ring introduces steric hindrance which prevents μ-opioid affinity from increasing much further. As with other 3-substituted fentanyl derivatives such as ohmefentanyl, the stereoisomerism of lofentanil is very important, with some stereoisomers being much more potent than others.
Adrenalone is an adrenergic agonist used as a topical vasoconstrictor and hemostatic. Formerly, it was also used to prolong the action of local anesthetics. It is the ketone form of epinephrine (adrenaline). Contrary to epinephrine, adrenalone mainly acts on alpha-1 adrenergic receptors, but has little affinity for beta receptors. The drug is largely obsolete, being superseded by other hemostatics such as thrombin, fibrinogen, and vasopressin analogues.
Acetoxyketobemidone (O-Acetylketobemidone) is an opioid analgesic that is an acetylated derivative of ketobemidone. It was developed in the 1950s during research into analogues of pethidine and was assessed by the United Nations Office on Drugs and Crime but was not included on the list of drugs under international control, probably because it was not used in medicine or widely available. Nevertheless, acetoxyketobemidone is controlled as an ester of ketobemidone, which is included in Schedule I of the Single Convention on Narcotic Drugs of 1961.
Methylketobemidone is an opioid analgesic that is an analogue of ketobemidone. It was developed in the 1950s during research into analogues of pethidine and was assessed by the United Nations Office on Drugs and Crime but was not included on the list of drugs under international control, probably because it was not used in medicine or widely available.
Picenadol (LY-97435) is a 4-phenylpiperidine derivative that is an opioid analgesic drug developed by Eli Lilly in the 1970s.
R-4066 (Spirodone) is a drug which is an analogue of the opioid analgesic methadone, or more accurately norpipanone, where the metabolically labile dimethylamino group has been replaced by a piperidinospiro group. Developed by Janssen Pharmaceutica, it is around 212x more potent than methadone as an analgesic in animal tests, with an effective oral dosage of 0.07 mg/kg, but is shorter acting, with a duration of action of around 3 hours. If the ketone function is reduced and acetylated, the racemate 106 x methadone and has an analgesic duration of 20.5 hours compared to 8 hours for methadone.
JDTic is a selective, long-acting ("inactivating") antagonist of the κ-opioid receptor (KOR). JDTic is a 4-phenylpiperidine derivative, distantly related structurally to analgesics such as pethidine and ketobemidone, and more closely to the MOR antagonist alvimopan. In addition, it is structurally distinct from other KOR antagonists such as norbinaltorphimine. JDTic has been used to create crystal structures of KOR [ PDB: 4DJH, 6VI4].
4-Fluoropethidine is a drug that is a derivative of pethidine (meperidine), which combines pethidine's opioid analgesic effects with increased monoamine reuptake inhibition. It is around 50% less potent than pethidine as an opioid analgesic, but conversely is 50% more potent as a dopamine reuptake inhibitor, with other derivatives such as the 4-iodo and 3,4-dichloro analogues being even more potent dopamine reuptake inhibitors again. However none of these compounds substitute for cocaine or produce stimulant effects in animals, suggesting that they still act primarily as opioid analgesic drugs in practice. Its action and degree of relation to pethidine means that it may be controlled in those countries which have laws about controlled-substance analogues; it is not itself listed in the Controlled Substances Act 1970.
Samidorphan, is an opioid antagonist which in the form of olanzapine/samidorphan is used in the treatment of schizophrenia and bipolar disorder. Samidorphan reduces the weight gain associated with olanzapine. Samidorphan is taken by mouth.
βk-2C-B is a novel psychedelic substance. It is the beta (β) ketone structural analogue of 2C-B, a psychedelic drug of the 2C family. It is used as a recreational drug, usually taken orally. βk-2C-B is a controlled substance in Canada, Germany, Switzerland, and the United Kingdom.
2-Fluorodeschloroketamine is a dissociative anesthetic related to ketamine. Its sale and use as a designer drug has been reported in various countries. It is an analogue of ketamine where the chlorine group has been replaced by fluorine. Due to its recent emergence, the pharmocological specifics of the compound are mostly unclear.
