In Canada, tryptophan is sold as a prescription drug to treat mood disorders (such as bipolar disorder, depression). It is usually used with other medicines. It works to make the mood more stable and reduce extremes in behavior by restoring the balance of certain natural substances (serotonin, melatonin) in the brain. Tryptophan is a natural substance (amino acid) found in high-protein foods and milk.
In the US, tryptophan is sold as a dietary supplement. It has been used to support mood, relaxation, and restful sleep. If you are taking other medications that may affect serotonin (such as many antidepressants), do not take tryptophan without talking with your doctor first. A very serious (possibly fatal) drug interaction may occur. Your doctor should closely monitor you. See also Side Effects section.
Some supplement products have been found to contain possibly harmful impurities/additives. Check with your pharmacist for more details about the brand you use.
The US FDA has not reviewed this product for safety or effectiveness. Consult your doctor or pharmacist for more details.

How to use L-Tryptophan Oral
If your doctor has prescribed this medication, take it by mouth with a meal or snack, usually 3 to 4 times a day or as directed by your doctor. Taking this medication with food helps reduce side effects such as nausea.
Dosage is based on your medical condition and response to treatment. Your doctor may adjust your dose to find the best dose for you. Do not take this medication more often, increase your dose, or stop taking it without first consulting your doctor. Your condition will not improve faster and your risk of side effects will increase.
If your doctor has prescribed this medication, use it regularly to get the most benefit from it. To help you remember, take it at the same times each day.
If you are using tryptophan as a dietary supplement, take this product by mouth as directed. Follow all directions on the product package. If you are uncertain about any of the information, consult your doctor or pharmacist.
Consult your doctor or pharmacist before using this product for any mental/mood disorders such as depression or bipolar disorder. Your condition may require medical attention or prescribed medication.
Tell your doctor if your condition persists or worsens. If you think you may have a serious medical problem, seek immediate medical attention.

Nausea, loss of appetite, dizziness, drowsiness, headache, or dry mouth may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.
If your doctor has prescribed this medication, remember that he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Tell your doctor immediately if any of these rare but very serious side effects occur: muscle stiffness/spasms, severe muscle aches/pain, unusual/inappropriate sexual urges, shakiness (tremor), unusual weakness.
This product may rarely cause a very serious condition called serotonin syndrome. The risk increases when tryptophan is taken with certain other drugs such as lithium, tramadol, triptans used to treat migraine headaches (such as sumatriptan, zolmitriptan), antidepressants including MAOIs, TCAs, SSRIs (such as citalopram, fluoxetine, paroxetine), and NSRIs (such as duloxetine, venlafaxine), or a certain drug to treat obesity (sibutramine). Before taking this product, tell your doctor if you take any of these medications. Serotonin syndrome may be more likely when you start taking any of these medications or when you increase the dose. Seek immediate medical attention if you develop any of the following symptoms:
fast heartbeat, loss of coordination/difficulty walking, high fever, sweating, mental/mood changes (such as strange thoughts, unusual excitement, extreme anxiety, confusion), severe nausea/vomiting/diarrhea, twitchy muscles.
A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any of the following symptoms of a serious allergic reaction: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Before taking tryptophan, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
This product should not be used if you have the following medical condition. Before using this medicine, consult your doctor or pharmacist if you have a history of: a certain muscle reaction to tryptophan (eosinophilia-myalgia syndrome).
Before using this medication, tell your doctor or pharmacist your medical history, especially of: personal/family history of diabetes, digestive problems (such as achlorhydria, malabsorption), low-protein diet, scleroderma.
This drug may make you dizzy or drowsy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Limit alcoholic beverages.
During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.
It is not known whether this drug passes into breast milk. Consult your doctor before breast-feeding.

See also Side Effects section.
Drug interactions may increase side effects or cause your medications to stop working properly. However, if your doctor has directed you to use this product, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. While using this product, do not start, stop, or change the dosage of any medicine before checking with your doctor or pharmacist first.
This product should not be used with the following medications because very serious interactions may occur: sibutramine, sodium oxybate.
Do not take any MAO inhibitors (isocarboxazid, linezolid, methylene blue, moclobemide, phenelzine, procarbazine, rasagiline, selegiline, tranylcypromine) within 2 weeks before, during, or after treatment with this medication. In some cases a serious (possibly fatal) drug interaction may occur.
If you are currently using any of these medications listed above, tell your doctor or pharmacist before starting tryptophan.
Before using this product, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially of: levodopa, other drugs that may increase serotonin levels (including triptans such as sumatriptan, SSRIs such as paroxetine, TCAs such as amitriptyline), St. John\'s wort.
Tell your doctor or pharmacist if you also take drugs that cause drowsiness such as certain antihistamines (including diphenhydramine), anti-seizure drugs (such as carbamazepine), medicine for sleep or anxiety (such as alprazolam, diazepam, zolpidem), muscle relaxants, narcotic pain relievers (such as codeine), psychiatric medicines (such as chlorpromazine, risperidone, trazodone).
Check the labels on all your medicines (such as cough-and-cold products) because they may contain ingredients that may cause drowsiness. Ask your pharmacist about using those products safely.
This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.

If overdose is suspected, contact your local poison control center or emergency room immediately. US residents can call the US National Poison Hotline at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: seizures, loss of consciousness.

NOTES:
Do not share this medication with others. Keep all regular medical and laboratory appointments.

MISSED DOSE:
If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

STORAGE:
Store the Canadian product at room temperature between 59-86 degrees F (15-30 degrees C) away from light and moisture. Do not store in the bathroom. For the US product, refer to storage information printed on the package. If you have any questions about storage, ask your pharmacist. Keep all medicines away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.
Information last revised October 2011. Copyright(c) 2011 First Databank, Inc.