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What is L-tryptophan?
The use of dietary or herbal supplements in cultural and traditional settings may differ from what is accepted in Western medicine. When considering the use of any dietary or herbal supplement, it is best to talk with your medical doctor. You may also talk with a naturopathic doctor or other practitioner trained in the use of herbal medicines. L-tryptophan is an amino acid that is made from plant or animal sources. It has been used to treat sleep problems (insomnia), anxiety, depression, premenstrual syndrome, attention deficit disorder, and for smoking cessation and other conditions. L-tryptophan may also be used for purposes other than those listed here.

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What are the possible side effects of L-tryptophan?

Stop using L-tryptophan and 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.

Other less serious side effects are more likely to occur. Talk with your doctor or care practitioner if you have any of these less serious side effects:

• dry mouth, heartburn, burping, gas;

• nausea, vomiting, diarrhea;

• feeling drowsy or light-headed;

• blurred vision;

• weakness, lack of coordination;

• headache; or

• lost appetite.

Side effects other than those listed here may also occur. Talk to your doctor or care practitioner about any side effect that seems unusual or that is especially bothersome.

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How should I take L-tryptophan?
Take L-tryptophan exactly as directed on the label, or as your doctor or care practitioner has prescribed it for you. Do not use more of the product than recommended, and do not use it for longer than recommended. Do not give any herbal/health supplement to a child without first talking to the child's doctor. Store L-tryptophan at room temperature away from moisture and heat.

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What is the most important information I should know about L-tryptophan?
L-tryptophan is sold as a dietary supplement and is not subject to U.S. Food and Drug Administration (FDA) guidelines for safe manufacturing. Some of the L-tryptophan sold in the U.S. is imported from manufacturers in other countries. The FDA has not determined the safety, purity, or effectiveness of L-tryptophan. All of the potential risks and benefits of using this product are therefore unknown. Dietary supplements and herbal "medicines" may contain toxic or impure ingredients that could be harmful to your health. Dietary and herbal supplements should be purchased from a reliable source such as a pharmacy or well-known retail store. Do not use any dietary or herbal product that does not list a manufacturer and/or distributor name and address on the label.

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What happens if I miss a dose?
Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and take the next regularly scheduled. Do not take extra L-tryptophan to make up the missed dose.

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What other drugs will affect L-tryptophan?
L-tryptophan may interact with other medicines. Before taking L-tryptophan, tell your doctor or care practitioner if you are also using: medicine for depression such as St. John's wort, citalopram (Celexa), escitalopram (Lexapro), fluoxetine (Prozac), paroxetine (Paxil), sertraline (Zoloft), amitriptyline (Elavil), imipramine (Tofranil), venlafaxine (Effexor), and others; a monoamine oxidase inhibitor (MAOI) such as tranylcypromine (Nardil), phenelzine (Parnate), selegiline (Eldepryl), or isocarboxazid (Marplan);

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Can I take this if I am pregnant or trying to get pregnant or if I am breastfeeding?

Do not use L-tryptophan without telling your doctor or care practitioner if you are pregnant. It is not known whether L-tryptophan would be harmful to an unborn baby.

Do not use L-tryptophan without telling your doctor or care practitioner if you are breast-feeding a baby. It is not known whether L-tryptophan would be harmful to a nursing infant.

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What does my medication look like?
L-tryptophan is available over-the-counter (without a prescription) under. Many different brand or generic forms may be available. Ask your pharmacist any questions you have about this product, especially if it is new to you. Dietary supplements and herbal "medicines" may contain toxic or impure ingredients that could be harmful to your health. Dietary and herbal supplements should be purchased from a reliable source such as a pharmacy or well-known retail store. Do not use any dietary or herbal product that does not list a manufacturer and/or distributor name and address on the label.

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What happens if I overdose?
Seek emergency medical attention if you think you have used too much of this product.

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What should I discuss with my health care provider before taking L-tryptophan?
L-tryptophan is sold as a dietary supplement and is not subject to U.S. Food and Drug Administration (FDA) guidelines for safe manufacturing. Some of the L-tryptophan sold in the U.S. is imported from manufacturers in other countries. The FDA has not determined the safety, purity, or effectiveness of L-tryptophan. All of the potential risks and benefits of using this product are therefore unknown. Before taking L-tryptophan, tell your doctor or other care practitioner if you have: liver disease;

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Can I stop taking the medication if I feel better?
As a general rule, you should always take your medications exactly as prescribed and do not change the dosage or stop taking the medication without first discussing it with your healthcare provider.

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I am on so many medications; do I have to take them all?
This is called polypharmacy—many different medications being used at the same time by one person. Sometimes, being on multiple medications is acceptable and appropriate but at other times it may be problematic. If you are receiving your medications from multiple physicians you need to ensure that they all know what medications you are taking. The best way to do this is to make a list of all the medications you are currently using, including all nutritional supplements, homeopathic remedies, vitamins and over-the-counter drugs (if possible, also include all the diseases you have been diagnosed with). Give a copy to every doctor who takes care of you so they have it on file, this way they can avoid duplicating medications and perhaps even try to consolidate some. After every doctor's visit remember to update the list accordingly. Also, as much as you possibly can, try to use the same pharmacy to fill all your prescriptions, this way any potential drug interactions can be caught and averted.

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