L-tryptophan is important for many organs in the body. L-tryptophan is not made by the body and must be consumed from the diet. After absorbing L-tryptophan from food, the body converts some of it to 5-HTP and then to serotonin. Serotonin is a hormone that transmits signals between nerve cells. Changes in serotonin levels in the brain can affect mood.
People use L-tryptophan for severe PMS symptoms, depression, insomnia, and many other conditions, but there is no good scientific evidence to support any of these uses.
Uses & Effectiveness ?
Possibly Ineffective for
In 1989, L-tryptophan was linked to cases of a neurological condition called eosinophilia-myalgia syndrome (EMS). But these cases might be due to contamination. About 95% of all EMS cases have been traced to L-tryptophan produced by a single manufacturer in Japan.
There isn't enough reliable information to know if L-tryptophan is safe when taken for more than 3 weeks.
Special Precautions and Warnings
Breast-feeding: There isn't enough reliable information to know if L-tryptophan is safe to use when breast-feeding. Stay on the safe side and stick to food amounts.
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.
Do not take this combination
Dextromethorphan (Robitussin DM, and others) interacts with L-TRYPTOPHAN
L-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-TRYPTOPHAN
L-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-TRYPTOPHAN
L-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-TRYPTOPHAN
Taking 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-TRYPTOPHAN
Sedative 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-TRYPTOPHAN
Tramadol (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.
Be cautious with this combination
Keep in mind that some dietary supplement products might not list L-tryptophan separately on the label. Instead, it might be listed under niacin. Niacin is measured in niacin equivalents (NE). 60 mg of L-tryptophan is the same as 1 mg NE.
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