Phenethylamine

Phenethylamine
Systematic (IUPAC) name
phenylethan-2-amine
Identifiers
CAS number	64-04-0
ATC code	?
PubChem	1001
ChemSpider	13856352
Chemical data
Formula	C8H11N
Mol. mass	121.18 g/mol
SMILES	eMolecules & PubChem
Synonyms	2-phenylethylamine, β-phenylethylamine
Pharmacokinetic data
Bioavailability	?
Metabolism	MAO-A, MAO-B, ALDH, DBH, CYP2D6
Half life	~5-10 minutes
Excretion	?
Therapeutic considerations
Pregnancy cat.	?
Legal status	Uncontrolled
Routes	Oral

Phenethylamine (PEA) is a natural monoamine alkaloid, trace amine, and psychoactive drug with stimulant effects. In the mammalian central nervous system, phenethylamine is believed to function as a neuromodulator or neurotransmitter. It is biosynthesized from the amino acid phenylalanine by enzymatic decarboxylation. Besides mammals, phenethylamine is found in many other organisms and foods such as chocolate, especially after microbial fermentation. It is sold as a dietary supplement for purported mood and weight loss-related therapeutic benefits; however, orally ingested phenethylamine is usually inactive on account of extensive first-pass metabolism by monoamine oxidase (MAO) into phenylacetic acid, preventing significant concentrations from reaching the brain.^[1][2]

Substituted phenethylamines, substituted amphetamines, and substituted methylenedioxyphenethylamines (MDxx) are a series of broad and diverse classes of compounds derived from phenethylamine that include stimulants, psychedelics, and entactogens, as well as anorectics, bronchodilators, decongestants, and antidepressants, among others.

Chemistry

Phenethylamine is an aromatic amine, which is a colorless liquid at room temperature. It is soluble in water, ethanol, and ether. Similar to other low-molecular-weight amines, it has a fishy odor. Upon exposure to air, it forms a solid carbonate salt with carbon dioxide. Phenethylamine is strongly basic and forms a stable crystalline hydrochloride salt with a melting point of 217 °C. Phenethylamine is also a skin irritant and possible sensitizer.

Phenethylamine has an inactive constitutional isomer 1-phenylethylamine, which itself has two stereoisomers: (R)-(+)-1-phenylethylamine and (S)-(-)-1-phenylethylamine.

Pharmacology

Phenethylamine, similarly to amphetamine, acts as a releasing agent of norepinephrine and dopamine.^[3][4][5] 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 disorder (ADHD)^[6] and often in clinical depression, while levels are elevated in schizophrenia.^[7]

Pharmacokinetics

Phenylethylamine's half life is 5–10 minutes.^{[8][dubious – discuss]} Phenylethylamine is metabolized by MAO-A ^[2], MAO-B ^[1], aldehyde dehydrogenase and dopamine-beta-hydroxylase.^[8] Phenylethylamine brain levels can be increased by a 1000 fold when taking an MAO Inhibitor and 3-4 times when taken by itself.^{[9][dubious – discuss]} Alcohol and THC increase phenylethylamine levels by a 4 fold.^{[9][dubious – discuss]}

Chocolate theory of love

In the early 1980s, researcher Michael Liebowitz, author of the popular 1983 book The Chemistry of Love, remarked to reporters that "chocolate 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."^[10] However, as noted earlier, phenethylamine is rapidly metabolized by the enzyme MAO-B, preventing significant concentrations from reaching the brain, thus contributing no perceptible psychoactive effect without the use of an monoamine oxidase inhibitor (MAOI).

See also

• Amphetamine
• Alexander Shulgin
• PiHKAL

References

External links

• Book II of PiHKAL online
• Phenethylamine entry in PiHKAL • info
• Review and summary of PiHKAL, including table of 300+ phenethylamines: ascii postscript
• A Structural Tour of PiHKAL