supplement benefit and side effects, what is the best way to use this amino
acid? by Ray Sahelian, M.D.
Available in 250 mg, 500 mg, and 750 mg pills.
What are the risk of taking this amino acid in high dosages?
L Tyrosine, is not an essential amino acid since it can be made from the amino acid phenylalanine. It is converted into dopamine and norepinephrine. Supplementation with both tyrosine and phenylalanine leads to alertness and mental arousal. Mind Power Rx works in a smooth, effective way, to increase alertness and focus, along with mood.
Phenylalanine and tyrosine are sometimes prescribed as antidepressants, usually in combination with other nutrients and herbs that have mood elevating properties. Some doctors also recommend these amino acids for appetite control. If you have an interest in an appetite suppressant, consider Diet Rx, an all natural herbal formula. Phenylalanine may trigger the release of an appetite-suppressing hormone in the gut called cholecystokinin. Most individuals who take either of these amino acids notice improved alertness, arousal, and mood, and slight loss in appetite. I have a few patients who occasionally take a small amount of these amino acids, such as 100 to 250 mg, in the morning as a substitute for coffee.
Phenylalanine converts to L Tyrosine, followed by L-dopa which in turns is metabolized to dopamine which can convert into norepinephrine and then to epinephrine.
Lets say you take 100 mg of tyrosine pill, how much of
it is converted into L-dopa?
I have not seen any human studies to determine what percentage of this amino acid is converted in L-dopa. There is probably a great deal of individual variability.
• Memory and Mood
• Mental clarity
• Alertness and Focus
The herbs in this formula include: Bacopa, Fo-Ti, Ginkgo biloba, Ginseng, Mucuna pruriens, and Reishi. The nutrients and vitamins in Mind Power Rx include Acetyl-l-carnitine, Carnitine, Carnosine antioxidant, Choline, DMAE, Inositol, Pantothenic acid, Tyrosine, and Vinpocetine.
Side effects, caution, danger, risk
L Tyrosine side effects can include overstimulation, restlessness, anxiety, and insomnia. Rapid heart beat, heart palpitations or arrhythmias are potential side effects that occur from high doses. These can occur in sensitive individuals in as low a dose as 200 to 500 mg.
Given that you personally feel that high dosages of
tyrosine cause several adverse affects, is there ANY
regulation or FDA recommended dosage that is approved for this medicine? I have
had enormous problems with it in the past that are too dramatic to even begin to
You ask a good question that deserves a somewhat philosophical answer. There are no guidelines for supplement dosage recommendations since any such guidelines would be somewhat arbitrary and open to significant differences of opinion between scientists and doctors. And how do we know that government officials are any more knowledgeable (or honest) than medical doctors, nutritionists, or scientists? There are thousands of herbs and individual supplements, and tens of thousands or more of different combination formulas. How can any independent or governmental organization ever keep up with this? If such strict guidelines are placed on supplements dosages, why not them limit alcohol sale to only sex ounces per person since there would be, and is, a serious risk in drinking a lot more? What about limiting aspirin use since it can cause stomach ulcers and thousands of people are hospitalized each year for stomach bleeds. What about limiting sales of sugar-laden sodas that cause obesity and diabetes in our children? What about stopping people from skiing downhill since each weekend there are many people who get hurt on the slopes, some with permanent injuries? We live in a society that should accept that there are risks to some of the actions we take or some of the products and foods we ingest. If we were to tightly regulate every little detail of a citizen's life, we would no longer have the freedoms we currently enjoy. Each citizen is responsible for their own health and to learn as much about a food, drink, supplement, or medicine before they ingest it' and to learn as much about the risks of a physical activity or sport before engaging in that activity.
L Tyrosine may help some people in their fight against depression, but dosages above 500 mg, in some people, may cause anxiety, restlessness and rapid heart rate. I prefer other supplements for depression, including 5-HTP, SAM-e, St. John's wort, and fish oils. Two combination products that are helpful for mood, mental clarity, and energy are Mind Power Rx and MulitiVit Rx.
Review and summary, dosage
Tyrosine is an amino acid that can be used in the mornings to enhance alertness and focus. Too high a dose can cause side effects such as irritability, restlessness, anxiety, and heart rhythm problems. Some users find that it enhances their mood. N-Acetyl-Tyrosine is an alternative. Less of a dose of acetyl-tyrosine is required to achieve the same effects. You have the option to open a capsule and take a portion if the 500 mg makes you feel too much on the edge and nervous.
Focus and concentration
I have always suffered from concentration problems and I strongly feel that this has hindered my ability to follow through on various time-bound work and thinking. I have been taking 500mg of L-Tyrosine in the morning and afternoon. It has had a positive effect on my focusing, but have decided to try reducing my dosage since I feel it's somewhat hindered more spontaneity. Do you think it's detrimental to the metabolism of tyrosine into dopamine to drink caffeine..
High dosages of this amino acid supplement can cause restlessness, anxiety and insomnia which can be aggravated by consuming caffeinated drinks.
Grey hair, any
I read about your article about tyrosine amino acid, i found it great. That’s is why I wanted to consult you. Actually , my doctor advised me to take L-tyrosine supplements for treatment for grey hair. I have been taking it for more than 8 months with no effects. I just want to ask if L-tyrosine amino acid is really useful for this condition?
I do not believe tyrosine supplements are helpful as a treatment for grey hair.
Are you aware of any contraindication regarding the use of l-tyrosin in a person who has homocystinuria?
Not that I am aware of. Homocystinuria is an inherited disorder of the metabolism of the amino acid methionine, often involving cystathionine beta synthase.
I am concerned that excessive consumption of may contribute to schizophrenia (by contributing to the manufacture of norepinephrine which is implicated in schizophrenia). Can taking tyrosine trigger this condition in someone who doesn't have it? is there a risk?
We have not seen any evidence of such risk and have not heard of any such case studies.
Interactions with prescription
Are you aware of any adverse reactions that will occur when a person takes daily 50 mg Paxil, 450 mg Oxcarbazepine (Trileptal) divided into 150mg and 300mg doses, 4 mg Ativan (Lorazepam) and recently added Topamax (topiramate) started at 50 mg, eventually, to 200mg daily? I have been giving this person 500 mg of L-Tyrosine twice daily.
It is not easy to predict adverse effects since different people taking the same medications can have different benefits and side effects but we advise caution when mixing supplements and prescription meds.
Last year after taking Prozac for many years I decided to add L-tyrosine to my daily supplements. I added about 900 mg a day. Soon after that I developed what's been diagnosed as "tics".
Lack of behavioural effects after acute tyrosine depletion in healthy volunteers.
J Psychopharmacol. 2005.
In this study, we investigated the effects of brain dopamine depletion, through acute l-tyrosine and phenylalanine depletion, on plasma prolactin, mood and neuropsychological function in 12 normal subjects. In a randomized, double-blind, cross-over design, subjects received two amino-acid drinks separated by a week, a nutritionally balanced mixture (Bal) and on the other occasion a tyrosine and phenylalanine deficient mixture. The plasma ratio of tyrosine and phenylalanine to the other large neutral amino acids decreased significantly on the tyrosine and phenylalanine deficient mixture and there was an increase in plasma prolactin concentration relative to the balanced drink in the seven subjects for whom results were available for both occasions. Acute tyrosine depletion did not alter mood as measured by visual analogue scale ratings, and measures of memory, attention and behavioural inhibition were also unaffected. Our results are consistent with acute dietary tyrosine depletion causing a reduction in brain dopamine neurotransmission but raise questions about how robust or consistent the effects are on psychological function.
If the amino acid L-Tyrosine converts to L-Dopa, then would taking it produce the same effect or result as taking mucuna pruriens herb?
Not really. Mucuna pruriens has many other compounds in it.
considering taking N-Acetyl Tyrosine (mornings 200mg) and tryptophan (evenings
500mg) for treatment of mild depression and insomnia. I was wondering whether
SAM-e can be taken in addition?
It may be ok for some while others may get serious side effects. Much depends on dosage, individual tolerance, food intake, other medicines that you take, age, smoking, exercise patterns, sleep patterns, etc. It is a good idea to first learn how each supplements works by itself before combining.
Q. I went to a boarding school for three years where I averaged about 5 hrs of sleep every night. On top of this I was subjected to the physical stresses of mandatory sports, and ever present cold. I think the result is that I became a walking zombie. My awareness and attention drastically suffered, my emotions somewhat froze, and I developed obsessive compulsive disorder. After taking a sufficiently large dose of MDMA, I noticed that I became aware of the world in a way similar to how I had experienced it before boarding school. I concluded that I needed to redevelop my serotonin system, so I started taking 100mg 5htp on a daily basis. I noticed that my mood was better, especially when I took little breaks from it (I was pleased to learn that you recommend this practice). I also decided to experiment with my dopamine system, so I tried n-acetyl-l tyrosine. Immediately, I noticed an improved ability to perceive color. After a lot of trial and error, I found it best to take the n-acetyl-l tyrosine in two daily doses of 75mg. These two supplements have greatly helped, in the depression/anxiety, with which I was recently diagnosed.
A. Thanks for emailing your interesting story.
Q. I continue to learn from your book, Mind Boosters. It is the one source that I continually return to when exploring nutritional approaches. My question concerns tyrosine supplements. I have recently begun taking Acetyl L-Tyrosine, one 300 mg. tablet in the morning. It seems to increase energy, and even give a little boost in the area of verbal fluency (an area that I am very interested in improving). I seem to "feel like talking" more than I normally would, and the words seem to come a little more easily. However...I'm having a lot of trouble sleeping, even with this small (I think) dosage, I seem to have a "wired" feeling. I would hate to give up the benefits of tyrosine.
A. 300 mg of acetyl-tyrosine is actually, in my opinion, a high dose. Acetyl-tyrosine is probably much more active that tyrosine by itself. The alertness it produces does cause insomnia. A lower dosage may reduce the side effects.
Q. I have read a lot on your web site about the cautions of 5-HTP and would like to ask about whether there are any risks of using l tyrosine in the long-term. For me, this supplement really helps with my mood but I would like to know whether the amino acid is safe for daily consumption at a high dose (12 grams). I do not experiences any side-effects from this amino acid and have not read any reports of toxicity ever occurring from its use.
A. Twelve grams of tyrosine is an extremely high dose. Side effects could include irritability, anxiety, heart irregularities and perhaps, over the long run, tyrosine could have a pro oxidant effect on certain brain cells, but this is just a hypothesis. Tyrosine seems to be more effective in those whose depression is due to low dopamine levels. It's probably best to not use one particular nutrient to treat depression for prolonged periods but to alternate different ones such as St. John's wort, SAMe, 5-HTP, etc.
Q. Why is it so hard to get l-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. Since each person is unique in their requirement, it is okay to open capsules and take a portion.
Q. Having had fibromyalgia for almost 20 years, I had already investigated 5-HTP, but had seen a couple of articles warning that it contracts the arteries and should never be given to anyone with high cardiac risk factors or arterial spasm. I have a high risk ratio, high blood pressure and have had arterial spasms in cold weather, before I started taking high dose Magnesium....that stopped the spasms and also stopped the PVC's and chest pain from my regurgitating MVP. My former holistic doctor insisted I needed to take a supplement which contained both 5HTP and L tyrosine in large amounts. He dismissed the risks for both 5HTP and tyrosine as not true. He believed fibromyalgia to be a deficiency of neurotransmitters, which I regard as merely one of the many symptoms of the illness. Within 3 weeks I was having paroxysmal atrial fibrillation, PVC's, and PSVT attacks, and had to be placed on a cardiac event monitor (which is how the PSVTs were diagnosed). I could not even walk across a room without help, and when going outside into cold air, I was brought to my knees gasping from spasms. Every time I fell asleep, I would wake up repeatedly with PSVT's accompanied by horrifying dysautonomic symptoms. I stopped the product and slowly recovered over a period of about 2 months, except that PSVTs have become a permanent part of my illness now, and I must take Verapamil ER daily to keep them manageable. I no longer dare to drive a car or even walk our dogs because of these attacks. Ablation is not an option due to the dysautonomia, and the 3 leaking valves I have, as well as my allergy to all of the useful antibiotics for preventing BE in MVP patients, and an inability to take any pain med but Tylenol, due to the large amt. of Clonidine I must take for my high blood pressure. The product I took had high amounts of 5-HTP 300 mg and Tyrosine: 3,000 mg.
Q. I have had low grade depression in the past and
found tyrosine to be highly effective for me. Now with a 5 month old and the
winter season, I am feeling a bit low again and wondering if it is safe to take
tyrosine while I am nursing. My son’s health is ultimately more important, but I
would like to improve my mood as well, hopefully without prescription
A. Since we have not come across research regarding the use of tyrosine during nursing, it is difficult to make a recommendation.
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 no blood studies or other tests that can be done to find out which supplement will provide you with better results.
Q. I have been taking L Tyrosine for about 7 years to
help with central serous retinopathy. However, over the past two year I have
suffered terrible insomnia and never made a connection. Thanks to looking at
your site and the great information I see the connection. Do you think that the
tyrosine 500mg dosage that I have been taking for 7 years is a little to high?
A. We can't say if the tyrosine is the cause of your insomnia, but tyrosine has the potential to cause sleep problems.
Q. When I take L-tyrosine I seem to have intestinal
problems, such as gas and lose bowels. Is this a common side effect with L
A. Tyrosine has many side effects, the most common being irritability and rapid heart beat, but gastrointestinal symptoms can also occur. A lower dose tyrosine may not cause these side effects.
Why is it recommended that tyrosine be taken at
least 30 minutes before a meal or 2 hours after a meal?
Tyrosine cannot easily cross the blood brain barrier if there are many other competing amino acids in the blood stream which occur after eating a meal. Therefore, on an empty stomach, tyrosine can be absorbed well and cross the blood brain barrier. However, tyrosine side effects are higher when this approach is taken, therefore a lower dosage would minimize this. Hence, to notice the effects from a tyrosine supplement, one can take a higher amount of tyrosine with food, or a smaller amount on an empty stomach.
Even a small portion of beef contains more tyrosine
than most supplements. Why shouldn't I just eat a burger?
When individual amino acids are taken by themselves, they have a different affect on the body and mind as opposed to taken in combination as a supplement or in food. A dose of tyrosine, for instance, can cause alertness, whereas if the same amount is ingested in beef, it would not cause alertness since it would be mixed with many other competing amino acids.
I have seen an ad for Glycyl-L-Tyrosine. How is it
Glycyl-L-Tyrosine is a new one for me. I don't know much about it and have not seen human studies with it.
I've just found your tyrosine site after having
severe heart problems with arrhythmia. I was diagnosed with high cholesterol and
also raised TSH.
After reducing the rapid pulse and arrhythmia and being discharged, the doctors
varied in opinion re the level of TSH (only 6 6 ) and said was not too high. And
said heart was okay. But I was still extremely breathless even on just sitting.
Any exertion is difficult (and I was extremely fit and active).
I then thought back to what I'd done and had been taking 5htp and other vitamins
/ amino acids for a few months. Then about 4 weeks ago added in tyrosine
(self-medicated) then got exhausted, breathless, insomnia. Put it down to other
things, stress / work. Increased dose to 1000mg and increased 5htp to 3 x 50mg
per day. Symptoms got drastically worse, could hardly move and ended up in
hospital. Stopped medication. Then tried to piece this together. Then looked on
internet and found your site. So, please advise others as you are of the dangers
of tyrosine. I, like presumably others, thought I knew better and being vitamins
- could not do any damage. Secondly are you able to please answer whether the
breathlessness and rapid heart beat will disappear or have I done irreversible
damage. I am getting better each day, particularly on sitting but walking or any
exertion can be problematic.
If the problem was due to the misuse of supplements such as tyrosine, then the condition should reverse with time. However, we have no way of determining what your cardiac situation is without knowing all the study results including heart tests. We wish you optimal healing.
Thank you for the paragraph above. We have become a
country that depends on babysitters and sometimes babysitters aren't so nice. I
live in Asia most of the time and find it so refreshing that many of the people
that we Americans consider poor and downtrodden are much more intelligent about
their health than we have become. Personal responsibility for an individual's
health has migrated to 'corporations' that promise that they are taking care of
us. I love being aware of my own health and the life I lead. I don't smoke
anymore, but I do juice, take supplements if need be, drink too much wine,
exercise, and I PICK MY OWN POISONS! If you get my drift. Wake up America.
I came across your article today on L-Tyrosine and would like some information if you would be able to help me. For a month I have been taking L-Tyrosine. I take 500mg in the AM and 1000mg in the PM. I also take a B-complex and C with rosehips with it as I read these are needed to help with absorption. The main reason I started taking it is because I have low blood preassure (generaly 90/95 over 70/65) I have virtigo and the only answer I seem to get is that it is due to the low blood pressure which no one is concerned about. I do experiance some anxiety issues and who wouldn't mind losing some weight so it has other benifits that worked for me as well. I have not had my blood preassure checked in the past month but I do appear to be having less room spinning. My question is, is there a problem with 1500mg of L-Tyrosine or is there a better answer?
L tyrosine pills, in high dosages, can cause heart rhythm disturbances in some people, and if taken later in the day may cause shallow sleep.
How much more potent is N-acetyl-Tyrosine
compared to the same amount of L-tyrosine? I have severe problems with anhedonia
and bought N-acetyl to try and raise dopamine levels.
It's hard to say. I have not seen studies comparing the two. In my limited experience, I did find acetyl tyrosine to be more potent, but I can't quantify it easily. You may wish to try them yourself with the same dosage on different occasions to see how they compare.