D, L-Phenylalanine is an essential amino acid that plays an important role in mood, memory, and mental alertness. It is available in three different forms – L-, D- and DL-. The L- form is the most common and the type in which it is incorporated into the body’s proteins. The D- form acts as a painkiller and the DL- a combination of the two (DL-Pheine).
L-phenylalanine is an essential amino acid, meaning that we need it for life and our bodies can’t manufacture it from other chemicals and thus must be obtained through the diet. Phenylalanine is used in different biochemical processes to produce neurotransmitters, dopamine, norepinephrine, and epinephrine. It is claimed that phenylalanine can promote sexual arousal, and there is evidence that phenylalanine can increase mental alertness and release hormones affecting appetite. D-phenylalanine has been shown to inhibit the metabolism of opiate-like substances called enkephalins in the brain. It is claimed that DL-phenylalanine is effective in the treatment of chronic pain. It is best not to take your phenylalanine supplement at the same time as a high-protein meal.