Last updated: March 15, 2017


Essential amino acids are usually the building blocks for numerous enzymatic actions and effects within the body. Phenylalanine affects numerous systems within the brain and supplementing with DL-phenylalanine can increase perceived energy, focus, concentration, and reduce feelings of depression and memory loss.

What makes DL-phenylalanine special are the letters “D” and “L”. The L-phenylalanine found in nature (foods like meat and fish) can be helpful, but the D-phenylalanine is a manmade mirror molecule made in a laboratory. Combined, they contribute to improved memory and learning ability [1] and increase mood boosting chemicals like dopamine and norepinephrine.

Also Known As


Editors’ Thoughts on DL-Phenylalanine

I’ve never tried this (either natural form or synthetic), though the combination of synthetic phenylalanine forms and natural forms is intriguing to me. This seems relatively untested as of now, but that isn’t necessarily a bad thing.

I do take DL-phenylalanine when consuming Qualia, but that is the only interaction that I have with the compound thus far and I haven’t had any negative effects.

Mansal Denton, Nootropedia Editor


Benefits of DL-Phenylalanine

The primary benefits of DL-phenylalanine seem to be as a potent dopamine and adrenaline enhancer. The molecule acts as a precursor for these chemicals, which is considered the mechanism for improving mood and reducing symptoms of depression in some people [2].

A study as early as 1977 in the Journal of Neuron Transmission, showed that 12 out of 20 patients suffering from depression could be discharged after using DL-phenylalanine in the dose range of 75 – 200 mg / day.

While there is no research to directly compare DL-phenylalanine with increases in focus and attention, the combination of adrenaline and dopamine are typically the two most important factors in increasing focus and concentration. One would reasonably assume a benefit of DL-phenylalanine is increased focus and concentration.

Another study of DL-phenylalanine showed that the nutrient binds to glutamate AMPA receptors, which improve the communication between synapses in the brain. This has the effect of increasing memory speed and learning ability [3].

Finally, there are a host of benefits of DL-phenylalanine from an anecdotal perspective on internet communities like Reddit and Longecity. See the Selected Community Experiences section below.

Side Effects of DL-Phenylalanine

There are not many known side effects of DL-phenylalanine, though some people complain of stimulation beyond comfort. This might be related to dosage in addition to their other supplementation and dietary habits (or personal brain chemistry), however.

Some people complain of tolerance as a side effect of DL-phenylalanine, but this may not be applicable to everyone. Also, some parts of the DL-phenylalanine mixture do not end up well absorbed (by the brain or body) and are quickly excreted by the urine.

DL-Phenylalanine Dosage

Most products where you can buy DL-phenylalanine come in a dose range of 1 – 400 mg per day. There isn’t much literature on the proper DL-phenylalanine dosage as this will vary greatly depending on the person and desired effect.

It might be a good idea to start with 2-300 mg of the supplemental DL-phenylalanine as a beginner.

How and Where to Buy DL-Phenylalanine

There are supposed to be some pain reducing effects of DL-phenylalanine, which does have some evidence [4]. Although this is not commonly known, there is a possibility you can find DL-phenylalanine at a nearby grocery or health food store because of the pain-reducing effects.

In general, it would be best to find a solution online. There are two main ways to buy DL-phenylalanine including as a specific mixed compound or as part of a greater nootropic stack. For the first option, this is a DL-phenylalanine product that we trust. You can also receive 300 mg of DL-phenylalanine in the Qualia stack.

Selected Community Experiences

I went through a full bottle that I had bought from a Whole Foods. I loved it. Gave me a huge energy and mood boost. Can’t rule out placebo but isn’t that often the case? I recently bought l-phenylalanine thinking that the L was what was giving the pleasant effects but haven’t been impressed at all. I pretty much stopped taking it…” [5] – sonic_rukal

Thumbs up for DLPA in my experience. Energy boost and calm feel overall; no side effects that I can tell. Fwiw, never tried it with hordenine…” [6] – grab_bag_2776

References (Click to Expand)
  1. http://pubs.acs.org/doi/abs/10.1021/jm950028z
  2. https://www.ncbi.nlm.nih.gov/pubmed/335027
  3. http://pubs.acs.org/doi/abs/10.1021/jm950028z
  4. http://www.medical-hypotheses.com/article/S0306-9877(99)91031-9/abstract
  5. https://www.reddit.com/r/Nootropics/comments/31ciok/dlphenylalanine_experiences/
  6. Ibid.


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