Naloxone

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Naloxone

Naloxone is a drug

Medication

A pharmaceutical drug, also referred to as medicine or medicament, can be loosely defined as any substance intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease....
used to counter the effects of opioid

Opioid

Drug overdose

The term drug overdose describes the ingestion or application of a drug or other substance in quantities greater than are recommended or generally practiced....
, for example heroin

Heroin

Heroin is a opioid synthesized from morphine, a derivative of the opium poppy. It is the 3,6-acetate ester of morphine . The white crystalline form is commonly the hydrochloride salt diacetylmorphine hydrochloride, however heroin Freebase may also appear as a white powder....
or morphine

Morphine

Morphine is a highly potent opiate analgesic Medication, is the principal active agent in opium, and is considered to be the prototypical opioid....
overdose. Naloxone is specifically used to counteract life-threatening depression of the central nervous system and respiratory system. It is marketed under various trademarks including Narcan, Nalone, and Narcanti, and has sometimes been mistakenly called "naltrexate." It is not to be confused with Naltrexone

Naltrexone

Opioid receptor

Opioid receptors are a group of G-protein coupled receptors with opioids as ligands. The endogenous opioids are dynorphins, enkephalins, endorphins, endomorphins and nociceptin....
antagonist

Receptor antagonist

A receptor antagonist is a type of receptor ligand or drug that does not provoke a biological response itself upon binding to a Receptor , but blocks or dampens agonist-mediated responses....
with qualitatively different effects, used for dependence treatment rather than emergency overdose treatment.

Pharmacodynamics
Naloxone has an extremely high affinity for µ-opioid receptor

Opioid receptor

Opioid receptors are a group of G-protein coupled receptors with opioids as ligands. The endogenous opioids are dynorphins, enkephalins, endorphins, endomorphins and nociceptin....
s in the central nervous system

Central nervous system

The central nervous system is the part of the nervous system that functions to coordinate the activity of all parts of the bodies of multicellular organisms....
.

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Encyclopedia

Naloxone is a drug

Medication

Opioid

Drug overdose

The term drug overdose describes the ingestion or application of a drug or other substance in quantities greater than are recommended or generally practiced....
, for example heroin

Heroin

Morphine

Naltrexone

Opioid receptor

Opioid receptors are a group of G-protein coupled receptors with opioids as ligands. The endogenous opioids are dynorphins, enkephalins, endorphins, endomorphins and nociceptin....
antagonist

Receptor antagonist

Pharmacodynamics

Naloxone has an extremely high affinity for µ-opioid receptor

Opioid receptor

Central nervous system

The central nervous system is the part of the nervous system that functions to coordinate the activity of all parts of the bodies of multicellular organisms....
. Naloxone is a µ-opioid receptor competitive antagonist

Competitive antagonist

A competitive antagonist is a receptor antagonist that binds to a Receptor but does not activate the receptor. The antagonist will compete with available agonist for receptor binding sites on the same receptor....
, and its rapid blockade of those receptors often produces rapid onset of withdrawal

Withdrawal

Withdrawal, also known as withdrawal/abstinence syndrome, refers to the characteristic signs and symptoms that appear when a drug that causes physical dependence is regularly used for a long time and then suddenly discontinued or decreased in dosage....
symptoms. Naloxone also has an antagonist action, though with a lower affinity, at ?- and d-opioid receptors.

Chemistry

Naloxone is synthesized

Chemical synthesis

In chemistry, chemical synthesis is purposeful execution of chemical reactions in order to get a product , or several products. This happens by physics and chemical manipulations usually involving one or more reactions....
from thebaine

Thebaine

Thebaine is an opiate alkaloid. A minor constituent of opium, thebaine is chemically similar to both morphine and codeine, but has stimulatory rather than depressant effects, causing strychnine-like convulsions at higher doses....
. The chemical structure

Chemical structure

A Chemical structure includes molecular geometry, electronic structure and crystal structure of a chemical compound. Molecular geometry refers to the spatial arrangement of atoms in a molecule and the chemical bonds that hold the atoms together....
of naloxone resembles that of oxymorphone

Oxymorphone

Oxymorphone or 14-Hydroxydihydromorphinone is a powerful semi-synthetic opioid analgesic first developed in Germany circa or about 1914, patented in the USA by Endo Pharmaceuticals in 1955 and introduced to the United States market in January 1959 and other countries around the same time....
, the only difference being the substitution of the N

Amine

Amines are organic compounds and functional groups that contain a base nitrogen atom with a lone pair. Amines are derivative s of ammonia, wherein one or more hydrogen atoms are replaced by organic substituents such as alkyl and aryl groups....
-methyl group

Functional group

In organic chemistry, functional groups are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules....
with an allyl

Allyl

An allyl group is an alkene hydrocarbon group with the formula H2C=CH-CH2-. It is made up of a vinyl group, CH2=CH-, attached to a methylene -CH2....
(prop-2-enyl) group. The name naloxone has been derived from N-allyl and oxymorphone.

Administration

Naloxone is most commonly injected intravenously for fastest action. The drug acts after about two minutes, and its effects may last about 45 minutes. It can also be administered via intramuscular or subcutaneous injection. Use of a wedge device (nasal atomizer) attached to a syringe to create a mist delivering the drug to the nasal mucosa may also be utilized, although this solution is more likely utilized outside of a clinical facility.

Uses

Naloxone has been distributed as part of emergency kits to heroin users, and this has been shown to reduce rates of fatal overdose. Projects of this type are under way in San Francisco, New Mexico

New Mexico

New Mexico is a U. S. State located in the Southwestern United States of the United States. Inhabited by Native Americans in the United States populations for many centuries, it has also has been part of the Spanish Empire viceroyalty of New Spain, part of Mexico, and a U.S....
, Philadelphia, New York State, Baltimore, Boston, Los Angeles

Los Ángeles

Los ?ngeles is the Capital of the Biob?o Province, in the municipality of the same name, in Regions of Chile VIII , in the center-south of Chile....
, Milwaukee, and Chicago

Chicago

Chicago is the largest city in the U.S. state of Illinois and the Midwestern United States, as well as the List of United States cities by population city in the United States with more than 2.8 million residents....
, with pilot projects started in Scotland

Scotland

conventional_long_name = ScotlandAlba|common_name= Scotland|image_flag = Flag of Scotland.svg|flag_width = 130px...
in 2006.

The drug also blocks the action of pain-lowering endorphin

Endorphin

Endorphins are endogenous opioid polypeptide compounds. They are produced by the pituitary gland and the hypothalamus in vertebrates during strenuous exercise, excitement, pain, and orgasm, and they resemble the opiates in their abilities to produce analgesia and a sense of well-being....
s which the body produces naturally. The likely reason for this is that these endorphins operate on the same opioid receptors. Naloxone is capable of blocking a placebo

Placebo

The placebo effect is a phenomenon in medicine where the results of a medical treatment are affected by their symbolism, and not just their medical value....
pain-lowering response, both in clinical and experimental pain, if the placebo is administered together with a hidden or blind injection of naloxone.

While naloxone is still often used in emergency treatments for opioid overdose, its clinical use in the long-term treatment of opioid addiction

Addiction

The term "addiction" is used in many contexts to describe an obsession, compulsion, or excessive physical dependence or psychological dependence, such as: drug addiction, video game addiction, crime, alcoholism, compulsive overeating, problem gambling, computer addiction, pornography addiction, etc....
is being increasingly superseded by naltrexone

Naltrexone

Naltrexone is an opioid receptor receptor antagonist used primarily in the management of alcohol dependence and opioid dependence. It is marketed in generic form as its hydrochloride salt, naltrexone hydrochloride, and marketed under the trade names Revia and Depade....
. Naltrexone is structurally similar but has a slightly increased affinity for ?-opioid receptors over naloxone, can be administered orally and has a longer duration of action.

Enteral naloxone has been successfully used in the reduction of gastritis

Gastritis

Gastritis is an inflammation of the lining of the stomach, and has many possible causes. The main acute causes are excessive alcohol consumption or prolonged use of nonsteroidal anti-inflammatory drugs such as aspirin or ibuprofen....
and oesophagitis

Esophagitis

Esophagitis is inflammation of the esophagus....
associated with opioid therapy in mechanically-ventilated acute care patients.

Naloxone is also being used as a secondary chemical in the U.S. Food and Drug Administration-approved medicine Suboxone. Suboxone and Subutex were created as part of a detox program to help opiate

Opiate

In medicine, the term opiate describes any of the narcotic alkaloids found in opium, as well as any derivatives of such alkaloids....
addicted patients stop using opiates. Suboxone contains four parts buprenorphine

Buprenorphine

Buprenorphine is a semi-synthetic opiate with agonist and receptor antagonist actions. Buprenorphine hydrochloride was first marketed in the 1980s by Reckitt & Colman as an analgesic, available generally as Temgesic 0.2 mg sublingual tablets, and as Buprenex in a 0.3 mg/ml injectable formulation....
and one part naloxone, while Subutex contains only buprenorphrine.

Naloxone was added to Suboxone in an effort to dissuade patients from grinding up the Suboxone tablet and using it as part of a combination of opiates that the user would inject into their body. Intravenously administered naloxone is supposed to block the effects of any opiates and cause the user to go into immediate withdrawal. However, buprenorphine has a higher affinity for the opiate receptors, and many users have reported that Suboxone is injectable without inducing withdrawal effects. Oral or sublingual administration affects only the gastronintestinal tract, and has the added benefit of helping to reverse constipation and lowered bowel motility caused by chronic medical use or abuse of a variety of opioids. Buprenorphine itself has less of an effect on the central nervous system and produces far less euphoria

Euphoria (emotion)

Euphoria is medically recognized as an emotional and mental state defined as a sense of great happiness and quality_of_life. Technically, euphoria is an affect , but the term is often colloquially used to define emotion as an intense, Wiktionary:transcendent happiness combined with an overwhelming sense of well-being....
than other opioid

Opioid

An opioid is a chemical substance that has a morphine-like action in the body. The main use is for analgesia. These agents work by binding to opioid receptors, which are found principally in the central nervous system and the gastrointestinal tract....
drugs, while still being effective in the treatment of pain. For this reason, buprenorphine is gaining acceptance in the treatment of chronic pain, as well as opioid addiction withdrawal, since it produces fewer side effects and less sedation. On the whole, it is a drug moderately useful in pain management that is further attractive due to its relative lack of desirability to opioid abusers. Currently, only certified addictionologists (physicians specializing in the treatment of drug addiction and dependence) are legally permitted to prescribe Suboxone or other drugs containing buprenorphine for the treatment of addiction, although suboxone or other drugs containing buprenorphine can be prescribed for any purpose other than addiction or maintenance by any licensed physician. Like methadone

Methadone

Methadone is a synthetic opioid, used medically as an analgesic, antitussive and a maintenance drug addiction#Anti-addictive drugs for use in patients on opioids....
, buprenorphine has only recently been approved for use in the management of pain, and likely restrictions on prescribing authority will be eased over time as buprenorphine sees wider use and acceptance by the medical profession, and concerns over diversion and abuse lessen.

The addition of naloxone to buprenorphine in Suboxone tablets is intended to prevent misuse and abuse by injection. However, the Naloxone in Suboxone does cause side effects in some people. These side effects include, but are not limited to, asthenia

Asthenia

Asthenia is a medical term denoting symptoms of physical weakness and muscle weakness.A condition in which the body lacks or has lost strength either as a whole or in any of its parts....
, chills, headache

Headache

In medicine a headache or wiktionary:cephalalgia is a symptom of a number of different conditions of the head and sometimes neck. Some of the causes are benign while others are medical emergencies....
, infection

Infection

An infection is the detrimental colonization of a host organism by a foreign species. In an infection, the infecting organism seeks to utilize the host resources to multiply ....
, pain

Pain

Pain, in the sense of physical pain, is a typical sensory experience that may be described as the unpleasant awareness of a noxious stimulus or bodily harm....
, abdominal pain

Abdominal pain

Abdominal pain can be one of the symptoms associated with transient disorders or serious disease. Making a definitive diagnosis of the cause of abdominal pain can be difficult, because many diseases can result in this symptom....
, back pain

Back pain

Back pain is pain felt in the Human back that usually originates from the muscles, nerves, bones, joints or other structures in the Vertebral column....
, withdrawal

Withdrawal

Vasodilation

Vasodilation refers to the widening of blood vessels resulting from relaxation of smooth muscle cells within the vessel walls, particularly in the large arteries, smaller arterioles and large veins....
, constipation

Constipation

Constipation, costiveness, or irregularity, is a condition of the digestive system in which a person experiences hard feces that are difficult to expel....
, diarrhea

Diarrhea

In medicine, diarrhea, also spelled diarrhoea , is characterized by frequent loose or liquid bowel movements. The spelling of "diarrhea" is an appropriation of the Greek "diarrhoia" meaning "a flowing through." ....
, nausea

Nausea

Nausea is the sensation of unease and discomfort in the stomach with an urge to vomit....
, vomiting

Vomiting

Vomiting is the forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose. Undesired vomiting may result from many causes, ranging from gastritis or poisoning to brain tumors, or elevated intracranial pressure....
, insomnia

Insomnia

Insomnia is a symptom of a sleep disorder characterized by persistent difficulty falling sleep or staying asleep despite the opportunity. Insomnia is a symptom, not a stand-alone diagnosis or a disease....
, and sweating

Sweating

Perspiration is the production of a fluid, consisting primarily of water as well as various dissolved solids , that is excreted by the sweat glands in the skin of mammals....
. Because of these side effects, the FDA recommends that doctors begin any chemical detox using Subutex, which does not contain any Naloxone. In this way, if for some reason the doctor moves the patient to Suboxone and the patient begins having side effects related to naloxone, the doctor can easily move the patient back to Subutex.

For these reasons and others, it has been reported that Subutex is easier to withdraw from than Suboxone.

Legal status

The patent

Patent

A patent is a set of exclusive rights granted by a state to an inventor or his assignee for a term of patent in exchange for a disclosure of an invention....
for Naloxone has expired and the drug is currently available in various generic

Generic drug

A generic drug is a medication which isproduced and distributed without patent protection. The generic drug may still have a patent on the formulation but not on the active ingredient....
forms.

Recreational use

Naloxone has also been known to cause a slight tingling feeling in the lower extremities. This is the rush of adrenaline that often follows an injection of naloxone. When used for recreational purposes, this has been found to be the main effect users strive for. Users often feel bloated and nauseated after the tingling effect leaves the body.

Identification

The CAS number of naloxone is 465-65-6; the anhydrous hydrochloride

Hydrochloride

In chemistry, hydrochlorides are salt s resulting, or regarded as resulting, from the reaction of hydrochloric acid with an organic Base . This is also known as muriate, derived from hydrochloric acid's other name: muriatic acid....
salt

Salt

A salt, in chemistry, is defined as the product formed from the neutralisation reaction of acids and base . Salts are ionic compounds composed of cations and anions so that the product is electrically electric charge ....
has CAS 357-08-4 and the hydrochloride salt with 2 molecules of water has CAS 51481-60-8.

External links

, by the International Programme on Chemical Safety