I know little about biochemistry but I had idea that is worh at least discussing...

Phenylethilamine is broken down probably by same enzimes as his active derivates,
but it is fairly inactive even in multi-gram doses.

So,is there any possibility that taking phenylethylamine with its active derivates
(substituted phenethylamines,substituted amphetamines and substituted methylenedioxyphenethylamines)
in big quantities(as adulerant for example) will "keep enzymes bussie" and thus make
substituted goodies last longer in organism?!

Shulgin himself said so in PIHKAL. At least it's inactive at the doses he tried. Highest he tried was 1600mg. It's funny it's a component of many fat-burning supplements

Since im pretty sure many active phenylethylamines such as amphetamine are not as subject to MAOI enough to warrent longer action by keeping the receptors busy I doubt you would experience much difference in the action of these by simply taking PEA.

I agree with TheChemist in that it must in someway be active. Shulgin was looking for hallucinations or stimulation of some kind. 2-Phenylethylamine is metabolised by MAO-b into Phenylacetaldahyde and further conversion by Aldehyde dehydrogenase enzyme to Phenylacetic acid and smaller amounts of Phenylethanol.

Hence in order to see what effect large amounts of Phenylethylamine would have on the body one should primarily find out what effects large amounts of Phenylacetic acid would have.

Hence in order to see what effect large amounts of Phenylethylamine would have on the body one should primarily find out what effects large amounts of Phenylacetic acid would have.

There are probably better things to do with that phenylacetic acid 

Thing that confuses me here is why MAO (monoamine oxidase) doesn't attack
active phenylethilamine derivates since thay are all monoamines!?
 

I seriously know just about nothing about pharmacology honestly but the question intrigued me so I searched a bit...Looks like the rings substituents affects the metabolism. Looks like that even amongst differents 2C compounds, affinities for both MAO enzymes change depending of the size of the 4-substituent. I have no idea what are the differences between MAO-A and MAO-B though. Medicinal chemistry is really interesting ....

I've included the paper by the way...It doesn't really answer to your question, but it's still pretty interesting

..."what effects large amounts of Phenylacetic acid would have."....Sedit



Reference Information


TOXICITY OF PHENYLACETIC ACID.

Phenylacetic acid in human body fluids: high correlation between plasma and cerebrospinal
fluid concentration values


Evaluation of Phenylacetic Acid For Use as an Ingredient in  Tobacco Products

http://www.cosmeticsdatabase.com/ingredient.php?ingred06=725865