L-tryptophan is an amino acid, a protein building block that can be found in many plant and animal proteins. L-tryptophan is called an “essential” amino acid because the body can’t make it. It must be acquired from food.
L-tryptophan is used for insomnia, sleep apnea, depression, anxiety, facial pain, a severe form of premenstrual syndrome called premenstrual dysphoric disorder (PMDD), smoking cessation, grinding teeth during sleep (bruxism), attention deficit-hyperactivity disorder (ADHD), Tourette’s syndrome, and to improve athletic performance.
Tryptophan and Your Brain
The blood-brain barrier determines which substances in your blood can pass into the brain. At least nine amino acids, including tryptophan, compete with one another for access to the same carrier that transports them across the barrier. The amino acids present in the highest amount in your blood are more likely to win the competition. Tryptophan occurs in the smallest amount in most proteins, so it has a hard time gaining access, according to the “Encyclopedia of Neuroscience.” You can increase tryptophan’s chances by consuming it with carbohydrates. Carbs trigger the release of insulin, which lowers the amount of other amino acids in your blood without affecting levels of tryptophan.
About 80 percent of the serotonin in your body is in your gut, where it regulates activity in your intestines, according to “Medical News Today.” The rest is in your brain, which is where tryptophan becomes essential. After tryptophan gets in your brain, it’s turned into serotonin. As a neurotransmitter, serotonin has a role in learning and memory. It also regulates appetite and mood. Low levels of serotonin can cause depression. Research exploring the potential for L-tryptophan to treat depression, however, has produced inconsistent results, according to the July 2011 issue of “Alternative Therapies in Health and Medicine.”
Regulates Sleep Cycles
After tryptophan is converted into serotonin, your body uses serotonin to produce the hormone melatonin. In this way, tryptophan helps regulate your sleep-wake cycle, because melatonin promotes sleep. The amount of melatonin produced is determined by the light in your environment: Levels of the hormone in your blood are low during the day, and they rise in response to the dark. Melatonin supplements help improve some sleep problems, such as those caused by jet lag and a condition called delayed sleep phase syndrome, but evidence for their ability to treat insomnia isn’t strong, according to the University of Rochester.
Your body converts tryptophan into the B vitamin niacin, which is essential for metabolizing food into energy and maintaining a healthy nervous system. Niacin deficiency only develops when your diet lacks tryptophan as well as niacin, according to the “Merck Manual.” But your body needs an adequate supply of vitamin B-6, riboflavin and iron to successfully make niacin from tryptophan, reports MedlinePlus. Most of the top sources of tryptophan — poultry, meat, fish, cheese, beans and nuts — also contain the other nutrients needed to make the conversion.
L-tryptophan is POSSIBLY UNSAFE when taken by mouth. It has been linked to over 1500 reports of eosinophilia-myalgia syndrome (EMS) and 37 deaths. EMS is a neurological condition with symptoms that include fatigue; intense muscle pain; nerve pain; skin changes; baldness; rash; and pain and swelling affecting the joints, connective tissue, lungs, heart, and liver. Symptoms tend to improve over time, but some people may still experience symptoms up to 2 years after they develop EMS. Some people report that their symptoms have never gone away completely.
In 1990, L-tryptophan was recalled from the market due to these safety concerns. After the limitation of L-tryptophan products, the number of EMS cases dropped sharply. The exact cause of EMS in patients taking L-tryptophan is unknown, but some evidence suggests it may be due to contaminated L-tryptophan products. About 95% of all EMS cases were traced to L-tryptophan produced by a single manufacturer in Japan. Currently, under the Dietary Supplement Health and Education Act (DSHEA) of 1994, L-tryptophan is available and marketed as a dietary supplement.
L-tryptophan can cause some side effects such as heartburn, stomach pain, belching and gas, nausea, vomiting, diarrhea, and loss of appetite. It can also cause headache, lightheadedness, drowsiness, dry mouth, visual blurring, muscle weakness, and sexual problems.
Special Precautions & Warnings:
Pregnancy and breast-feeding: L-tryptophan is LIKELY UNSAFE in pregnancy because it may harm the unborn child. Not enough is known about the safety of L-tryptophan during breast-feeding. Avoid using L-tryptophan during pregnancy and breast-feeding.
A white blood cell disorder called eosinophilia: L-tryptophan might make this condition worse. L-tryptophan has been associated with the development of eosinophilia-myalgia syndrome (EMS).
Liver or kidney disease: L-tryptophan might make these conditions worse since it has been associated with the development of eosinophilia-myalgia syndrome (EMS).
- Medications for depression (Antidepressant drugs) interacts with L-TRYPTOPHAN
L-tryptophan increases a brain chemical called serotonin. Some medications for depression also increase the brain chemical serotonin. Taking L-tryptophan along with these medications for depression might increase serotonin too much and cause serious side effects including heart problems, shivering, and anxiety. Do not take L-tryptophan if you are taking medications for depression.Some of these medications for depression include fluoxetine (Prozac), paroxetine (Paxil), sertraline (Zoloft), amitriptyline (Elavil), clomipramine (Anafranil), imipramine (Tofranil), and others.
- Medications for depression (MAOIs) interacts with L-TRYPTOPHAN
L-tryptophan increases a chemical in the brain. This chemical is called serotonin. Some medications used for depression also increase serotonin. Taking L-tryptophan with these medications used for depression might cause there to be too much serotonin. This could cause serious side effects including heart problems, shivering, and anxiety.Some of these medications used for depression include phenelzine (Nardil), tranylcypromine (Parnate), and others.
- Sedative medications (CNS depressants) interacts with L-TRYPTOPHAN
L-tryptophan might cause sleepiness and drowsiness. Medications that cause sleepiness are called sedatives. Taking L-tryptophan along with sedative medications might cause too much sleepiness.Some sedative medications include clonazepam (Klonopin), lorazepam (Ativan), phenobarbital (Donnatal), zolpidem (Ambien), and others.
- Dextromethorphan (Robitussin DM, and others) interacts with L-TRYPTOPHANL-Tryptophan can affect a brain chemical called serotonin. Dextromethorphan (Robitussin DM, others) can also affect serotonin. Taking L-tryptophan along with dextromethorphan (Robitussin DM, others), might cause there to be too much serotonin in the brain and serious side effects including heart problems, shivering and anxiety could occur. Do not take L-tryptophan if you are taking dextromethorphan (Robitussin DM, others).
- Meperidine (Demerol) interacts with L-TRYPTOPHANL-tryptophan increases a chemical in the brain called serotonin. Meperidine (Demerol) can also increase serotonin in the brain. Taking L-tryptophan along with meperidine (Demerol) might cause too much serotonin in the brain and serious side effects including heart problems, shivering, and anxiety.
- Pentazocine (Talwin) interacts with L-TRYPTOPHANL-tryptophan increases a brain chemical called serotonin. Pentazocine (Talwin) also increases serotonin. Taking L-tryptophan along with pentazocine (Talwin) might cause serious side effects including heart problems, shivering, and anxiety. Do not take L-tryptophan if you are taking pentazocine (Talwin).
- Phenothiazines interacts with L-TRYPTOPHANTaking L-tryptophan with phenothiazines can cause serious side effects including movement disorders.
Some phenothiazines include chlorpromazine (Thorazine), fluphenazine (Prolixin), trifluoperazine (Stelazine), thioridazine (Mellaril), and others.
- Sedative medications (Benzodiazepines) interacts with L-TRYPTOPHANSedative medications can affect the nervous system. L-tryptophan can also affect the nervous system. Taking L-tryptophan along with sedative medications can cause serious side effects. Do not take L-tryptophan if you are taking sedative medications. Some of these sedative medications include clonazepam (Klonopin), diazepam (Valium), lorazepam (Ativan), and others.
- Tramadol (Ultram) interacts with L-TRYPTOPHANTramadol (Ultram) can affect a chemical in the brain called serotonin. L-tryptophan can also affect serotonin. Taking L-tryptophan along with tramadol (Ultram) might cause too much serotonin in the brain and side effects including confusion, shivering, and stiff muscles could result.
L-Triptofano, L-Trypt, L-2-amino-3-(indole-3-yl) propionic acid, L-Tryptophane, Tryptophan