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. 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.
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.
Alfentanil is a potent but short-acting synthetic opioid analgesic drug, used for anaesthesia in surgery. It is an analogue of fentanyl with around one-fourth to one-tenth the potency, one-third the duration of action, and an onset of action four times faster than that of fentanyl. Alfentanil has a pKa of approximately 6.5, which leads to a very high proportion of the drug being uncharged at physiologic pH, a characteristic responsible for its rapid onset. It is an agonist at mu opioid receptors.
Kolokol-1 is a synthetic opioid developed for use as an aerosolizable incapacitating agent. The exact chemical structure has not yet been revealed by the Russian government. It was originally thought by some sources to be a derivative of the potent opioid fentanyl, most probably 3-methylfentanyl dissolved in an inhalational anaesthetic as an organic solvent. However, independent analysis of residues on the Moscow theater hostage crisis hostages' clothing or in one hostage's urine found no fentanyl or 3-methylfentanyl. Two much more potent and shorter-acting agents, carfentanil and remifentanil, were found in the samples. They concluded that the agent used in the Moscow theater hostage crisis contained two fentanyl derivatives much stronger than fentanyl itself, sprayed in an aerosol mist.
Butyrophenone is an organic compound with the formula C6H5C(O)C3H7. It is a colorless liquid. Called commonly butyrophenones, modified versions of butyrophenone are used to treat various psychiatric disorders such as schizophrenia, as well as acting as antiemetics.
Droperidol is an antidopaminergic drug used as an antiemetic and as an antipsychotic. Droperidol is also often used as a rapid sedative in intensive-care treatment, and where "agitation aggression or violent behavior" are present.
Trifluperidol is a typical antipsychotic of the butyrophenone chemical class. It has general properties similar to those of haloperidol, but is considerably more potent by weight, and causes relatively more severe side effects, especially tardive dyskinesia and other extrapyramidal effects. It is used in the treatment of psychoses including mania and schizophrenia. It was discovered at Janssen Pharmaceutica in 1959.
Bromperidol, sold under the brand names Bromidol and Impromen among others, is a typical antipsychotic of the butyrophenone group which is used in the treatment of schizophrenia. It was discovered at Janssen Pharmaceutica in 1966. An ester prodrug, bromperidol decanoate, is a long-acting form of bromperidol used as a depot injectable.
Azaperone is a pyridinylpiperazine and butyrophenone neuroleptic drug with sedative and antiemetic effects, which is used mainly as a tranquilizer in veterinary medicine. It is uncommonly used in humans as an antipsychotic drug.
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.
Moperone (Luvatren, since discontinued) is a typical antipsychotic of the butyrophenone class which is marketed in Japan for the treatment of schizophrenia. It is an antagonist for the D2 (Ki 0.7-1.9 nM), D3 (Ki 0.1-1 nM), and 5-HT2A (Ki 52 nM) receptors. It also has a high binding affinity for the sigma receptors.
The drug combination morphine/naltrexone is an opioid combination pain medication developed by King Pharmaceuticals for use in moderate to severe pain. The active ingredients are morphine sulfate and naltrexone hydrochloride; morphine being an opioid receptor agonist and naltrexone an opioid receptor antagonist. It is a schedule 2 controlled substance, and is intended for long-term pain caused by malignancy or where lower tiers of the pain management ladder have already been exhausted, and where medications such as oxycodone would otherwise have been indicated.
Lenperone (Elanone-V) is a typical antipsychotic of the butyrophenone chemical class. It was first reported as an emetic in 1974, and its use in treatment of acute schizophrenia was reported in 1975. Related early antipsychotic agents include declenperone and milenperone.
Fentanyl/fluanisone is a veterinary combination drug consisting of fentanyl and fluanisone for use in mice, rats, rabbits and guinea pigs.
Butyrfentanyl or butyrylfentanyl is a potent short-acting synthetic opioid analgesic drug. It is an analog of fentanyl with around one quarter of its potency. One of the first mentions of this drug can be found in document written by The College on Problem of Drug Dependence, where it is mentioned as N-butyramide fentanyl analog. This document also states that the article describing its clinical effects was published in 1987. It is an agonist for the μ-opioid receptors.
Acetylfentanyl is an opioid analgesic drug that is an analog of fentanyl. Studies have estimated acetylfentanyl to be fifteen times more potent than morphine, which would mean that despite being somewhat weaker than fentanyl, it is nevertheless still several times stronger than pure heroin. It has never been licensed for medical use and instead has only been sold as a designer drug. Acetylfentanyl was discovered at the same time as fentanyl itself and had only rarely been encountered on the illicit market in the late 1980s. However, in 2013, Canadian police seized 3 kilograms of acetylfentanyl. As a μ-opioid receptor agonist, acetylfentanyl may serve as a direct substitute for heroin or other opioids. Common side effects of fentanyl analogs are similar to those of fentanyl itself, which include itching, nausea and potentially serious respiratory depression, which can be life-threatening. Fentanyl analogs have killed hundreds of people throughout Europe and the former Soviet republics since the most recent resurgence in use began in Estonia in the early 2000s, and novel derivatives continue to appear.
The word neuroleptic originates from the Greek word lepsis ("seizure"). Antipsychotics were investigated by the anesthesiologists De Castro and Mundeleer who coined the term neuroleptanalgesia, an anesthetic process that involves combining a major neuroleptic tranquilizer/antipsychotic with a potent opioid analgesic to produce a detached, pain-free state. This technique was widely used from the 1960s onwards, initially using a combination of phenoperidine and haloperidol, which was subsequently replaced in the early 1980s by a combination of fentanyl and droperidol. Efforts were also made to develop compounds which combined both types of activity in a single molecule. Neuroleptanalgesia results in amnesia among some patients, but not all. The technique has become less popular with the advent of more modern procedural sedation drug combinations, though it is still rarely used today as a combination of 2.5 mg droperidol and 50 μg (micrograms) of fentanyl in a ratio of 50:1. This combination is characterized by immobility, analgesia, and variable amnesia.
Furanylfentanyl (Fu-F) is an opioid analgesic that is an analog of fentanyl and has been sold as a designer drug. It has an ED50 value of 0.02 mg/kg in mice. This makes it approximately one fifth as potent as fentanyl.
Acrylfentanyl (also known as acryloylfentanyl or Egyptenyl) is a highly potent opioid analgesic that is an analog of fentanyl and has been sold online as a designer drug. In animal studies the IC50 or half maximal inhibitory concentration for acrylfentanyl to displace naloxone is 1.4 nM, being slightly more potent than fentanyl itself (1.6 nM) as well as having a longer duration of action.
