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Brand Names:

Generic Name: L-tryptophan (Pronunciation: L TRIP toe fan)

• What is L-tryptophan ()?
• What are the possible side effects of L-tryptophan ()?
• What is the most important information I should know about L-tryptophan ()?
• What should I discuss with my health care provider before taking L-tryptophan ()?
• How should I take L-tryptophan ()?
• What happens if I miss a dose ()?
• What happens if I overdose ()?
• What should I avoid while taking L-tryptophan ()?
• What other drugs will affect L-tryptophan ()?
• Where can I get more information?

What is L-tryptophan ()?

L-tryptophan is an amino acid that is made from plant or animal sources.

L-tryptophan has been used in alternative medicine as an aid to treat sleep problems (insomnia), anxiety, depression, premenstrual syndrome, attention deficit disorder, and for smoking cessation and other conditions.

Not all uses for l-tryptophan have been approved by the FDA. L-tryptophan should not be substituted for medications prescribed for you by your doctor.

L-tryptophan is often sold as an herbal supplement. There are no regulated manufacturing standards in place for many herbal compounds and some marketed supplements have been found to be contaminated with toxic metals or other drugs. Herbal/health supplements should be purchased from a reliable source to minimize the risk of contamination.

It is dangerous to try and purchase l-tryptophan on the Internet or from vendors outside of the United States. The sale and distribution of l-tryptophan outside of the U.S. does not comply with the regulations of the Food and Drug Administration (FDA) for the safe use of this medication.

L-tryptophan may also be used for other purposes not listed in this product guide.

What are the possible side effects of L-tryptophan ()?

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

In 1989, a life-threatening condition called eosinophilia-myalgia syndrome (EMS) occurred in many people using L-tryptophan and some died from the condition. All of these people had taken L-tryptophan distributed by a company in Japan. This L-tryptophan was found to contain trace levels of impure ingredients. Since that time, the FDA has limited the availability of L-tryptophan in the U.S. However, the increased use of the Internet has made many dietary supplements available from non-U.S. sources.

There have been no published cases of EMS within the last several years, but you should be aware of the symptoms. Call your doctor at once if you have any of the following:

• severe muscle pain (most often in the shoulders, back, or legs);
• weakness, numbness, tingling, or burning pain (especially at night);
• tremors or twitching muscle movements;
• swelling in any part of your body;
• skin changes (dryness, yellowing, hardening);
• breathing difficulty; or
• uneven heartbeat.

Less serious side effects may include:

• dry mouth, heartburn, burping, gas;
• nausea, vomiting, diarrhea;
• feeling drowsy or light-headed;
• blurred vision;
• weakness, lack of coordination;
• headache; or
• lost appetite.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What is the most important information I should know about L-tryptophan ()?

Not all uses for l-tryptophan have been approved by the FDA. L-tryptophan should not be substituted for medications prescribed for you by your doctor.

L-tryptophan is often sold as an herbal supplement. There are no regulated manufacturing standards in place for many herbal compounds and some marketed supplements have been found to be contaminated with toxic metals or other drugs. Herbal/health supplements should be purchased from a reliable source to minimize the risk of contamination.

Use l-tryptophan as directed on the label, or as your healthcare provider has prescribed. Do not use this product in larger amounts or for longer than recommended.

It is dangerous to try and purchase l-tryptophan on the Internet or from vendors outside of the United States. The sale and distribution of l-tryptophan outside of the U.S. does not comply with the regulations of the Food and Drug Administration (FDA) for the safe use of this medication.

In 1989, a life-threatening condition called eosinophilia-myalgia syndrome (EMS) occurred in many people using L-tryptophan and some died from the condition. All of these people had taken L-tryptophan distributed by a company in Japan. This L-tryptophan was found to contain trace levels of impure ingredients. Since that time, the FDA has limited the availability of L-tryptophan in the U.S. However, the increased use of the Internet has made many dietary supplements available from non-U.S. sources.

There have been no published cases of EMS within the last several years, but you should be aware of the symptoms. Stop using L-tryptophan and call your doctor or care practitioner at once if you have any of these signs of EMS: severe muscle pain (most often in the shoulders, back, or legs); weakness, numbness, tingling, or burning pain (especially at night); tremors or twitching muscle movements; swelling in any part of your body; skin changes (dryness, yellowing, hardening); breathing difficulty; uneven heartbeat.

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