What other names is L-tryptophan known by?
L-Triptofano, L-Trypt, L-2-amino-3-(indole-3-yl) propionic acid, L-Tryptophane, Tryptophan.
What is L-tryptophan?
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
, facial pain
, a severe form of premenstrual syndrome
called premenstrual dysphoric disorder
), smoking cessation
, grinding teeth
(bruxism), attention deficit-hyperactivity
), Tourette's syndrome
, and to improve athletic performance.
Possibly Effective for...
- Treating premenstrual dysphoric disorder (PMDD). Taking 6 grams of L-tryptophan per day seems to decrease mood swings, tension, and irritability in women with PMDD.
- Smoking cessation (helping people quit smoking). Taking L-tryptophan seems to improve the effectiveness of conventional treatment for smoking cessation.
Possibly Ineffective for...
- Treating teeth grinding (bruxism).
- Treating facial pain.
- Improving athletic ability.
Insufficient Evidence to Rate Effectiveness for...
- Depression. Developing research suggests that L-tryptophan might improve the effectiveness of common medications for depression.
- Seasonal affective disorder (SAD). Early research suggests L-tryptophan might be helpful in SAD.
- Attention deficit-hyperactivity disorder (ADHD). There is some evidence that L-tryptophan levels are lower in children with ADHD; however, taking L-tryptophan supplements does not appear to improve ADHD symptoms.
- Treating sleep disorders. Taking L-tryptophan might decrease the amount of time it takes to fall asleep and improve mood in healthy people with sleep problems. There is also some evidence that taking L-tryptophan might decrease episodes in some people who periodically stop breathing during sleep (sleep apnea).
- Other conditions.
More evidence is needed to rate L-tryptophan for these uses.
Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).
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