DLPA Phenylalanine side effects
There may be a danger with phenylalanine in high doses. Some of the side effects include anxiety, restlessness, rapid heart beat, and potential heart palpitations.

Phenylketonuria
A rare metabolic disorder called phenylketonuria (PKU) occurs in people who are missing an enzyme that is needed to properly metabolize phenylalanine. Symptoms of PKU, which tend to appear between three and six months of age, include eczema, developmental delay, an abnormally small head, and hyperactivity. If it is not treated before three weeks of age, PKU can cause severe, irreversible mental retardation. In the United States, newborns are tested for PKU during the first 48 to 72 hours of life.

Forms of Phenylalanine
Several forms include dl phenylalanine d phenylalanine and l phenylalanine. We recently had a question regarding the form of phenylalanine:
 

Q. I noticed the Source Naturals phenylalamine product is the DL-phenylalanine version. You mention there are three kinds, the L, the D and then the DL-phenylalanine. Would you be able to tell me specifically what issues each of these targets? I have read Phenylalanine can help with things ranging from chronic pain to anxiety, depression, pms, so I would be interested to know what form addresses what exactly.
   A. Phenylalanine is an essential amino acid. L-Phenylalanine (LPA) is an electrically-neutral amino acid, one of the twenty common amino acids. L-Phenylalanine that is ingested is mostly hydroxylated to form the amino acid tyrosine, which is used in protein synthesis. D-phenylalanine (DPA) is the mirror form of L-phenylalanine and does not participate in protein biosynthesis although it is found in proteins. The biological activity of D-phenylalanine is not as well known as L-phenylalanine but is thought to have pain reducing properties or perhaps it enhances the pain reducing ability of pain killers when taken together. D-phenylalanine may also have mood lifting potential. DL-Phenylalanine is a combination of D-phenylalanine and L-phenylalanine and is promoted for mood lifting and pain reducing abilities. Clinical research in humans is quite limited and thus the anti-depressant and anti-pain role of phenylalanine has not been well-evaluated.
  
Phenylalanine in food
L-phenylalanine is found in foods that contain protein such as beef, poultry, fish, milk, eggs, dairy products, soy products, and some nuts and seeds. D-phenylalanine is synthesized in the laboratory and not found in food.   
 

DLPA Phenylalanine Emails
Q. Why is it so hard to get tyrosine, phenylalanine, and others in smaller doses? Everyone talks about the 500 mgs doses, I personally do much better with the low doses. Is it possible that lot of people would do better with the lower doses, as you talk about in your Mind Boosters book?
   A. It seems that the public thinks higher doses are better, and manufacturers respond to this by selling higher dose products, worried that other companies may grab a larger share of the market by selling higher dosage nutrients.

See a list of amino acids

Q. What does DLPA stand for?
     A. DLPA stands for dl phenylalanine.

Q. I have recently started researching DLPA and tyrosine and am wondering if there is any real reason to take BOTH, or if it is generally an either/or thing. I currently take tyrosine and iodine, along with high pot. liquid multi vit/min., essential fatty acids etc. I have a thyroid problem and my naturopath has me on tyrosine and iodine, but because I am pretty overweight I was looking into DLPA and am confused by the frequent references to take DLPA and tyrosine TOGETHER, when DLPA will just be turned into tyrosine anyway. Is there another use for DLPA, or is it always turned into tyrosine? And if it is always turned into tyrosine, why bother with both? And if only one should be taken at a time, which is preferred?
     A. DLPA does convert into tyrosine, but it can be metabolized in a different direction, too, including phenylpurivic acid and other metabolites. I personally don't see the need to take both tyrosine and phenylalanine. As to which one to choose, the best way is through trial and error since there are blood studies or other tests that can be done to find out which supplement will provide better results.

Q. In the last issue of your newsletter you talk about the side effects of aspartame and you mention that phenylalanine is one of its ingredients. Is phenylalanine dangerous? can phenylalanine cause cancer?
     A. A Phenylalanine supplement in high doses may cause heart rhythm abnormalities and anxiety. Long term studies are not available to tell us whether phenylalanine supplements taken for prolonged periods cause cancer.

Q. Is phenylalanine considered a smart pill?
     A. I don't think so. There are many other herbs and nutrients that I like, for instance acetylcarnitine, ginkgo, bacopa, etc.
 

Q, Can one take phenylalanine DLPA and L-Tyrosine at the same time? Can one take DLPA, L-Tyrosine, and 5-HTP at the same time?
   A. Firstly it is important to find out the dosage of DLPA that works for you without side effects, and then separately find out the dosage of tyrosine that works for you without side effects. If you combine both DLPA and tyrosine, the dosage of each should be about half of what was appropriate for each one separately. As to your second question, reactions to supplements become difficult to predict when more than 2 are used. Hence, adding 5HTP to dl phenylalanine and then adding 5HTP may be tolerated or cause unpleasant side effects depending on the person using it, other supplements used, other medications that might be taken together, a person's overall healthe, and most importantly the dosages that are used.

Q. I have a question about Tyrosine and phenylalanine. I read that if you take supplemental Tyrosine, you should make sure that it also contains Phenylalanine or take supplemental Phenylalanine. It also said that Phenylalanine must be present with Tyrosine in order to produce Tyrosine in the body. Do you agree? Or is it okay to just take Tyrosine alone?
   A. Depends on the reason these supplements are being used. In most cases there is no reason to use both, tyrosine works well by itself and there is no need to take both tyrosine and phenylalanine. But each condition is different, each person is different, and the dosage makes a significant difference.

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