How does L-tryptophan work?

L-tryptophan is naturally found in animal and plant proteins. L-tryptophan is considered an essential amino acid because our bodies can't make it. It is important for the development and functioning of many organs in the body. After absorbing L-tryptophan from food, our bodies convert it to 5-HTP (5-hyrdoxytryptophan), and then to serotonin.

Are there safety concerns?

L-tryptophan might not be safe. It 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.

There are concerns that L-tryptophan or impurities in L-tryptophan might cause swelling (inflammation) of the joints, skin, lungs, heart, and liver and other side effects, including death.

Do not take L-tryptophan if:
  • You are pregnant or breast-feeding.
  • You have a kidney disorder.
  • You have a liver disorder.
  • You have a white blood cell disorder called eosinophilia.

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