Phenethylamine (
PEA) is a
naturalA natural product is a chemical compound or substance produced by a living organism - found in nature that usually has a pharmacological or biological activity for use in pharmaceutical drug discovery and drug design...
monoamine
alkaloidAlkaloids are naturally occurring chemical compounds containing basic nitrogen atoms. The name derives from the word alkaline and was used to describe any nitrogen-containing base. Alkaloids are produced by a large variety of organisms, including bacteria, fungi, plants, and animals and are part of...
,
trace amineTrace amines are endogenous compounds structurally related to classical biogenic amines, such as catecholamines, serotonin and histamine. Trace amines include p-tyramine, β-phenylethylamine, tryptamine, octopamine, and 3-iodothyronamine, and are found in the nervous systems of animals from insects...
, and
psychoactive drugA psychoactive drug, psychopharmaceutical or psychotropic substance is a chemical substance that acts primarily upon the central nervous system where it alters brain function, resulting in changes in perception, mood, consciousness and behavior...
with
stimulantStimulants, also sometimes called psychostimulants, are psychoactive drugs which induce temporary improvements in either mental or physical function or both. Examples of these kinds of effects may include enhanced alertness, wakefulness, and locomotion, among others...
effects. In the mammalian
central nervous systemThe central nervous system is the part of the nervous system that functions to coordinate the activity of all parts of the bodies of bilaterian animals—that is, all animals more advanced than sponges or jellyfish. In vertebrates, the central nervous system is enclosed in the meninges. It contains...
, phenethylamine is believed to function as a neuromodulator or
neurotransmitterNeurotransmitters are endogenous chemicals which relay, amplify, and modulate signals between a neuron and another cell. Neurotransmitters are packaged into synaptic vesicles that cluster beneath the membrane on the presynaptic side of a synapse, and are released into the synaptic cleft, where they...
. It is biosynthesized from the
amino acidAmino acids are molecules containing an amine group, a carboxylic acid group and one of the twenty R-groups. These molecules are particularly important in biochemistry, where this term refers to alpha-amino acids with the general formula H
2NCHRCOOH, where R is an organic substituent...
phenylalaninePhenylalanine is an α-amino acid with the formula HO
2CCHCH
2C
6H
5. This essential amino acid is classified as nonpolar because of the hydrophobic nature of the benzyl side chain. The codons for
L-phenylalanine are UUU and UUC...
by enzymatic
decarboxylationDecarboxylation is any chemical reaction in which a carboxyl group is split off from a compound as carbon dioxide .- Common examples :Common biosynthetic decarboxylations of amino acids to amines are:* tryptophan to tryptamine...
. Besides mammals, phenethylamine is found in many other organisms and foods such as
chocolateChocolate comprises a number of raw and processed foods produced from the seed of the tropical cacao tree. Cacao has been cultivated for at least three millennia in Mexico, Central and South America, with its earliest documented use around 1100 BC...
, especially after
microbialA microorganism or microbe is an organism that is microscopic...
fermentationFermentation in food processing typically is the conversion of carbohydrates to alcohols and carbon dioxide or organic acids using yeasts, bacteria, or a combination thereof, under anaerobic conditions. A more restricted definition of fermentation is the chemical conversion of sugars into ethanol...
. It is sold as a
dietary supplementA dietary supplement, also known as food supplement or nutritional supplement, is a preparation intended to provide nutrients, such as vitamins, minerals, fiber, fatty acids or amino acids, that are missing or are not consumed in sufficient quantity in a person's diet...
for purported
moodA mood is a relatively long lasting emotional state. Moods differ from simple emotions in that they are less specific, less intense, and less likely to be triggered by a particular stimulus or event....
and
weight lossWeight loss, in the context of medicine, health or physical fitness, is a reduction of the total body mass, due to a mean loss of fluid, body fat or adipose tissue and/or lean mass, namely bone mineral deposits, muscle, tendon and other connective tissue...
-related therapeutic benefits; however,
oralThe word oral may refer to:As an adjective:* the mouth.* speech communication as opposed to writing.* oral schools use oralism to teach the deaf....
ly ingested phenethylamine is usually
inactiveIn chemical thermodynamics activity is a measure of the “effective concentration” of a species in a mixture. By convention, it is a dimensionless quantity. The activity of pure substances in condensed phases is normally taken as unity. Activity depends on temperature, pressure and composition of...
on account of extensive first-pass metabolism by
monoamine oxidaseMonoamine oxidases are enzymes that catalyze the oxidation of monoamines. They are found bound to the outer membrane of mitochondria in most cell types in the body. The enzyme was discovered by Mary Hare in the liver, and received the name of tyramine oxidase...
(MAO) into
phenylacetic acidPhenylacetic acid is an organic compound containing a phenyl functional group and an acetic acid functional group. It is a white solid with a disagreeable odor...
, preventing significant
concentrationIn chemistry, concentration is the measure of how much of a given substance there is mixed with another substance. This can apply to any sort of chemical mixture, but most frequently the concept is limited to homogeneous solutions, where it refers to the amount of solute in the solvent.To...
s from reaching the
brainThe brain is the center of the nervous system in all vertebrate, and most invertebrate, animals. Some primitive animals such as jellyfish and starfish have a decentralized nervous system without a brain, while sponges lack any nervous system at all...
.
Substituted phenethylamineThe substituted phenethylamines are a family of chemical compounds that contain the 2-phenylethylamine chemical structure and also have additional modifications at the phenyl ring, sidechain, and/or amino group...
s,
substituted amphetamineThe substituted amphetamines are a chemical class of stimulants, entactogens, hallucinogens, and other psychoactive drugs. They feature a phenethylamine core with a methyl group attached to the alpha carbon resulting in amphetamine, along with additional substitutions.-Chemical Derivatives:A large...
s, and
substituted methylenedioxyphenethylamineSubstituted methylenedioxy- phenethylamines make up a large chemical class of derivatives of the phenethylamines, which includes many psychoactive drugs that act as entactogens, psychedelics, and/or stimulants, as well as entheogens, and are used as research chemicals or designer drugs and as...
s (MDxx) are a series of broad and diverse classes of compounds derived from phenethylamine that include
stimulantStimulants, also sometimes called psychostimulants, are psychoactive drugs which induce temporary improvements in either mental or physical function or both. Examples of these kinds of effects may include enhanced alertness, wakefulness, and locomotion, among others...
s,
psychedelicA psychedelic substance is a psychoactive drug whose primary action is to alter the cognition and perception of the mind. Psychedelics are part of a wider class of psychoactive drugs known as hallucinogens, which also includes related substances such as dissociatives and deliriants...
s, and entactogens, as well as
anorecticAn anorectic or anorexic , also known as anorexigenic or appetite suppressant, is a dietary supplements and/or drug which reduces appetite, food consumption, and as a result, causes weight loss to occur.-List of Anorectics:Numerous pharmaceutical compounds are marketed as appetite suppressants.The...
s,
bronchodilatorA bronchodilator is a substance that dilates the bronchi and bronchioles, decreasing airway resistance and thereby facilitating airflow. Bronchodilators may be endogenous , or they may be medications administered for the treatment of breathing difficulties...
s,
decongestantA decongestant or nasal decongestant is a type of drug which is used to relieve nasal congestion.- Pharmacology :The vast majority of decongestants act via enhancing norepinephrine and epinephrine or adrenergic activity by stimulating the α-adrenergic receptors...
s, and
antidepressantAn antidepressant is a psychiatric medication used to alleviate mood disorders, such as major depression and dysthymia. Drugs including the monoamine oxidase inhibitors , tricyclic antidepressants , tetracyclic antidepressants , selective serotonin reuptake inhibitors , and serotonin-norepinephrine...
s, among others.
Chemistry
Phenethylamine is an aromatic amine, which is a colorless liquid at room temperature. It is soluble in water,
ethanolEthanol, also called ethyl alcohol, pure alcohol, grain alcohol, or drinking alcohol, is a volatile, flammable, colorless liquid. It is a psychoactive drug, best known as the type of alcohol found in alcoholic beverages and in modern thermometers. Ethanol is one of the oldest recreational drugs...
, and
etherDiethyl ether, also known as ether, ethyl ether and ethoxyethane, is a clear, colorless, and highly flammable liquid with a low boiling point and a characteristic odor. It is the most common member of a class of chemical compounds known generically as ethers. It is an isomer of butanol...
. Similar to other low-molecular-weight amines, it has a fishy odor. Upon exposure to air, it forms a solid
carbonateIn chemistry, a carbonate is a salt or ester of carbonic acid, characterized by the presence of the carbonate ion, or a carbonate functional group O=C2....
saltA salt, in chemistry, is an ionic compound, and can result from the neutralization reaction of acids and bases. Salts are ionic compounds composed of cations and anions so that the product is electrically neutral...
with
carbon dioxideCarbon dioxide is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. It is a gas at standard temperature and pressure and exists in Earth's atmosphere in this state...
. Phenethylamine is strongly
basicIn chemistry, a base is most commonly thought of as an aqueous substance that can accept hydrogen ions. Bases are also the oxides or hydroxides of metals. A soluble base is also often referred to as an alkali if hydroxide ions are involved. This refers to the Brønsted-Lowry theory of acids and bases...
and forms a stable crystalline
hydrochlorideIn chemistry, hydrochlorides are salts resulting, or regarded as resulting, from the reaction of hydrochloric acid with an organic base...
salt with a melting point of 217 °C. Phenethylamine is also a skin irritant and possible sensitizer.
Phenethylamine has an inactive constitutional isomer
1-phenylethylamine1-Phenylethylamine is a monoamine compound. Individual enantiomers of this basic compound are useful for performing chiral resolution of acidic compounds by forming diastereomeric salts....
, which itself has two stereoisomers: (
R)-(+)-1-phenylethylamine and (
S)-(-)-1-phenylethylamine.
Pharmacology
Phenethylamine, similarly to amphetamine, acts as a
releasing agentA releasing agent , or simply releaser, is a drug which induces the release of a neurotransmitter from the pre-synaptic neuron into the synapse, leading to an increase in the extracellular concentrations of the neurotransmitter...
of
norepinephrineNoradrenaline or norepinephrine is a catecholamine with dual roles as a hormone and a neurotransmitter....
and
dopamineDopamine is a neurotransmitter occurring in a wide variety of animals, including both vertebrates and invertebrates. In the brain, this phenethylamine functions as a neurotransmitter, activating the five types of dopamine receptors — D
1, D
2, D
3, D
4, and...
. For this reason, it has been called the "body's endogenous amphetamine".
Low concentrations of endogenous phenethylamine are found in those suffering from
attention-deficit hyperactivity disorderAttention-deficit hyperactivity disorder is a neurobehavioral developmental disorder. ADHD is primarily characterized by "the co-existence of attentional problems and hyperactivity, with each behavior occurring infrequently alone." While symptoms may appear to be innocent and merely annoying...
(ADHD) and often in
clinical depressionMajor depressive disorder is a mental disorder characterized by an all-encompassing low mood accompanied by low self-esteem, and loss of interest or pleasure in normally enjoyable activities...
, while levels are elevated in
schizophreniaSchizophrenia , from the Greek roots skhizein and phrēn, phren- is a psychiatric diagnosis that describes a mental disorder characterized by abnormalities in the perception or expression of reality...
.
Pharmacokinetics
Phenylethylamine's half life is 5–10 minutes.
Phenylethylamine is metabolized by MAO-A , MAO-B ,
aldehyde dehydrogenaseAldehyde dehydrogenases are a group of enzymes that catalyse the oxidation of aldehydes.Mitochondrial Aldehyde Dehydrogenase is a polymorphic enzyme responsible for the oxidation of aldehydes to carboxylic acids, which leave the liver and are metabolized by the body’s muscle and heart...
and dopamine-beta-hydroxylase.
Phenylethylamine brain levels can be increased by a 1000 fold when taking an MAO Inhibitor and 3-4 times when taken by itself.
Alcohol and THC increase phenylethylamine levels by a 4 fold.
Chocolate theory of love
In the early 1980s, researcher
Michael LiebowitzDr. Michael R. Liebowitz is a Columbia University psychiatrist and founder of the Anxiety Disorders Clinic, the first of its kind, at the New York State Psychiatric Institute. In 1985, he researched and highlighted an underrecognized status of Social Anxiety Disorder . This led to subsequent...
, author of the popular 1983 book
The Chemistry of Love, remarked to reporters that "
chocolateChocolate comprises a number of raw and processed foods produced from the seed of the tropical cacao tree. Cacao has been cultivated for at least three millennia in Mexico, Central and South America, with its earliest documented use around 1100 BC...
is loaded with PEA." This became the focus for an article in
The New York Times, which was then taken up by the wire services, then by magazine free-lancers, and evolved into the now-eponymous "chocolate theory of love." However, as noted earlier, phenethylamine is rapidly metabolized by the
enzymeEnzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process are called substrates, and the enzyme converts them into different molecules, called the products. Almost all processes in a biological cell need enzymes to occur at...
MAO-B, preventing significant concentrations from reaching the brain, thus contributing no perceptible psychoactive effect without the use of an
monoamine oxidase inhibitorMonoamine oxidase inhibitors are a class of powerful antidepressant drugs prescribed for the treatment of depression. They are particularly effective in treating atypical depression, and have also shown efficacy in smoking cessation....
(MAOI).
External links