Dipipanone
Encyclopedia
Dipipanone is a strong opioid
analgesic
drug, used for very severe pain in cases where other analgesics are unsuitable, for instance where morphine
is indicated but cannot be used due to the patient being allergic to morphine.
(Diconal, Wellconal) which has the advantage of reducing nausea, vomiting and histamine release associated with strong opioid therapy.
, the only structural difference being the N,N-dimethyl moiety of methadone being replaced with a piperidine
ring. Other related compounds with equivalent activity where the piperidine ring has been replaced by other groups, include the morpholine
derivative phenadoxone
, as well as the corresponding pyrrolidine
derivative. The general procedure for synthesis is illustrated by nucleophilic attack of diphenylacetonitrile on 2-chloro-1-piperidyl-propane. The resulting aminonitrile is then converted to the ethyl ketone with ethyl magnesium bromide by way of the ketimine which is hydrolyzed by cold aqueous acid.
marks the substance as "less suitable for prescribing" along with other older compounds such as pethidine
and pentazocine
with unusual abuse patterns. The combination with cyclizine leads to a very strong "rush" if the drug is injected, however the tablets contain insoluble binders which led to many limb amputations and some fatalities (as with temazepam
). During the late 1970s to early 1980s in the UK, many deaths were blamed on misuse of this preparation. As supplies became unavailable, opiate users would mix crushed methadone tablets or Physeptone ampoules with crushed Valoid (a cyclizine containing antihistamine) tablets, in an attempt to replicate the effect of Diconal.
Opioid
An opioid is a psychoactive chemical that works by binding to opioid receptors, which are found principally in the central and peripheral nervous system and the gastrointestinal tract...
analgesic
Analgesic
An analgesic is any member of the group of drugs used to relieve pain . The word analgesic derives from Greek an- and algos ....
drug, used for very severe pain in cases where other analgesics are unsuitable, for instance where morphine
Morphine
Morphine is a potent opiate analgesic medication and is considered to be the prototypical opioid. It was first isolated in 1804 by Friedrich Sertürner, first distributed by same in 1817, and first commercially sold by Merck in 1827, which at the time was a single small chemists' shop. It was more...
is indicated but cannot be used due to the patient being allergic to morphine.
Dosage forms
The main preparation of the drug commercially available is mixed with cyclizineCyclizine
Cyclizine is an antihistamine drug used to treat nausea, vomiting and dizziness associated with motion sickness, vertigo and post-operatively following administration of general anaesthesia and opioids.-Indications:...
(Diconal, Wellconal) which has the advantage of reducing nausea, vomiting and histamine release associated with strong opioid therapy.
Usage
Dipipanone is now unavailable in most countries of the world either by laws prohibiting its medicinal use as in the United States or by falling out of production as more modern analgesics took its market share. The UK, Ireland and South Africa are known to continue to use the substance but it is infrequently prescribed.Chemistry
Chemically, dipipanone belongs to the class of opioids called the 4,4-diphenylheptane-3-ones. It closely resembles methadoneMethadone
Methadone is a synthetic opioid, used medically as an analgesic and a maintenance anti-addictive for use in patients with opioid dependency. It was developed in Germany in 1937...
, the only structural difference being the N,N-dimethyl moiety of methadone being replaced with a piperidine
Piperidine
Piperidine is an organic compound with the molecular formula 5NH. This heterocyclic amine consists of a six-membered ring containing five methylene units and one nitrogen atom...
ring. Other related compounds with equivalent activity where the piperidine ring has been replaced by other groups, include the morpholine
Morpholine
Morpholine is an organic chemical compound having the chemical formula O2NH. This heterocycle, pictured at right, features both amine and ether functional groups. Because of the amine, morpholine is a base; its conjugate acid is called morpholinium...
derivative phenadoxone
Phenadoxone
Phenadoxone is an opioid analgesic of the open chain class invented in by Hoechst in 1947...
, as well as the corresponding pyrrolidine
Pyrrolidine
Pyrrolidine, also known as tetrahydropyrrole, is an organic compound with the molecular formula C4H9N. It is a cyclic secondary amine with a five-membered heterocycle containing four carbon atoms and one nitrogen atom...
derivative. The general procedure for synthesis is illustrated by nucleophilic attack of diphenylacetonitrile on 2-chloro-1-piperidyl-propane. The resulting aminonitrile is then converted to the ethyl ketone with ethyl magnesium bromide by way of the ketimine which is hydrolyzed by cold aqueous acid.
Medical use and recreational abuse
Prescription of dipipanone is discouraged apart from in exceptional circumstances, because of the perceived risk of abuse - the BNFBritish National Formulary
The British National Formulary is a medical and pharmaceutical reference book that contains a wide spectrum of information and advice on prescribing and pharmacology, along with specific facts and details about all medicines available on the National Health Service , including indication,...
marks the substance as "less suitable for prescribing" along with other older compounds such as pethidine
Pethidine
Pethidine or meperidine Pethidine (INN) or meperidine (USAN) Pethidine (INN) or meperidine (USAN) (commonly referred to as Demerol but also referred to as: isonipecaine; lidol; pethanol; piridosal; Algil; Alodan; Centralgin; Dispadol; Dolantin; Mialgin (in Indonesia); Petidin Dolargan (in Poland);...
and pentazocine
Pentazocine
Pentazocine is a synthetically prepared prototypical mixed agonist-antagonist narcotic drug of the benzomorphan class of opioids used to treat moderate to moderately severe pain...
with unusual abuse patterns. The combination with cyclizine leads to a very strong "rush" if the drug is injected, however the tablets contain insoluble binders which led to many limb amputations and some fatalities (as with temazepam
Temazepam
Temazepam is an intermediate-acting 3-hydroxy benzodiazepine. It is mostly prescribed for the short-term treatment of sleeplessness in patients who have difficulty maintaining sleep...
). During the late 1970s to early 1980s in the UK, many deaths were blamed on misuse of this preparation. As supplies became unavailable, opiate users would mix crushed methadone tablets or Physeptone ampoules with crushed Valoid (a cyclizine containing antihistamine) tablets, in an attempt to replicate the effect of Diconal.