Pethidine, also known as meperidine and sold under the brand name Demerol among others, is a fully 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, in 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.
Nalbuphine, sold under the brand names Nubain among others, is an opioid analgesic which is used in the treatment of pain. It is given by injection into a vein, muscle, or fat.
Dihydromorphine is a semi-synthetic opioid structurally related to and derived from morphine. The 7,8-double bond in morphine is reduced to a single bond to get dihydromorphine. Dihydromorphine is a moderately strong analgesic and is used clinically in the treatment of pain and also is an active metabolite of the analgesic opioid drug dihydrocodeine. Dihydromorphine occurs in trace quantities in assays of opium on occasion, as does dihydrocodeine, dihydrothebaine, tetrahydrothebaine, etc. The process for manufacturing dihydromorphine from morphine for pharmaceutical use was developed in Germany in the late 19th century, with the synthesis being published in 1900 and the drug introduced clinically as Paramorfan shortly thereafter. A high-yield synthesis from tetrahydrothebaine was later developed.
Phenoperidine, is an opioid analgesic which is structurally related to pethidine and is used clinically as a general anesthetic.
Piritramide(R-3365, trade names Dipidolor, Piridolan, Pirium and others) is a synthetic opioid analgesic that is marketed in certain European countries including: Austria, Belgium, Czech Republic, Slovenia, Germany and the Netherlands. It comes in free form, is about 0.75x times as potent as morphine and is given parenterally for the treatment of severe pain. Nausea, vomiting, respiratory depression and constipation are believed to be less frequent with piritramide than with morphine, and it produces more rapid-onset analgesia when compared to morphine and pethidine. After intravenous administration the onset of analgesia is as little as 1–2 minutes, which may be related to its great lipophilicity. The analgesic and sedative effects of piritramide are believed to be potentiated with phenothiazines and its emetic (nausea/vomiting-inducing) effects are suppressed. The volume of distribution is 0.7-1 L/kg after a single dose, 4.7-6 L/kg after steady-state concentrations are achieved and up to 11.1 L/kg after prolonged dosing.
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.
Methylnaltrexone, used in form of methylnaltrexone bromide, is a medication that acts as a peripherally acting μ-opioid receptor antagonist that acts to reverse some of the side effects of opioid drugs such as constipation without significantly affecting pain relief or precipitating withdrawals. Because MNTX is a quaternary ammonium cation, it cannot cross the blood–brain barrier, and so has antagonist effects throughout the body, counteracting effects such as itching and constipation, but without affecting opioid effects in the brain such as pain relief. However, since a significant fraction of opioid analgesia can be mediated by opioid receptors on peripheral sensory neurons, particularly in inflammatory conditions such as arthritis, traumatic or surgical pain, MNTX may increase pain under such circumstances.
Dezocine, sold under the brand name Dalgan, is an atypical opioid analgesic which is used in the treatment of pain. It is used by intravenous infusion and intramuscular injection.
Prodine is an opioid analgesic that is an analog of pethidine (meperidine). It was developed in Germany in the late 1940s.
Trimeperidine (Promedol) is an opioid analgesic that is an analogue of prodine. It was developed in the early 1950s in the USSR during research into the related drug pethidine.
Meprodine is an opioid analgesic that is an analogue of pethidine (meperidine). It is closely related to the drug prodine, the only difference being that meprodine has an ethyl group rather than a methyl at the 3-position of the piperidine ring.
Phenazocine is an opioid analgesic drug, which is related to pentazocine and has a similar profile of effects.
Propiram is a partial μ-opioid receptor agonist and weak μ antagonist analgesic from the ampromide family of drugs related to other drugs such as phenampromide and diampromide. It was invented in 1963 in the United Kingdom by Bayer but was not widely marketed, although it saw some limited clinical use, especially in dentistry. Propiram reached Phase III clinical trials in the United States and Canada.
Norpethidine is a 4-phenylpiperidine derivative that is both a precursor to, and the toxic metabolite of, pethidine (meperidine). It is scheduled by UN Single Convention on Narcotic Drugs. It is a Schedule II Narcotic controlled substance in the United States and has an ACSCN of 9233. The 2014 annual manufacturing quota was 11 grams (0.39 oz).
Benzethidine is a 4-phenylpiperidine derivative that is related to the clinically used opioid analgesic drug pethidine.
Etoxeridine is a 4-phenylpiperidine derivative that is related to the clinically used opioid analgesic drug pethidine (meperidine).
Furethidine is a 4-phenylpiperidine derivative that is related to the clinically used opioid analgesic drug pethidine (meperidine), but with around 25x higher potency. According to another source, Furethidine is 500/30 = 16.7 x the potency of pethidine.
Morpheridine (Morpholinoethylnorpethidine) is a 4-phenylpiperidine derivative that is related to the clinically used opioid analgesic drug pethidine (meperidine). It is a strong analgesic with around 4 times the potency of pethidine, and unlike pethidine, does not cause convulsions, although it produces the standard opioid side effects such as sedation and respiratory depression.
Pethidine intermediate A is a 4-phenylpiperidine derivative that is a precursor to the opioid analgesic drug pethidine (meperidine). It is not known to have any analgesic activity in its own right, however other derivatives of pethidine with a 4-cyano group in place of the carboxylate ethyl ester have been found to be active, so pethidine intermediate A might also show opioid effects. It is scheduled by UN Single Convention on Narcotic Drugs. It is a Schedule II Narcotic controlled substance in the United States and has an ACSCN of 9232. The 2014 annual manufacturing quota was 6 grammes.
Levallorphan, also known as levallorphan tartrate (USAN), is an opioid modulator of the morphinan family used as an opioid analgesic and opioid antagonist/antidote. It acts as an antagonist of the μ-opioid receptor (MOR) and as an agonist of the κ-opioid receptor (KOR), and as a result, blocks the effects of stronger agents with greater intrinsic activity such as morphine whilst simultaneously producing analgesia.
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