L-Theanine

Medically reviewed by Drugs.com. Last updated on Sep 9, 2024.

What are other common names?

• 5-N-Ethylglutamine
• Boletus badius
• Camellia sinensis
• Gamma-ethylamino-L-glutamic acid
• Gamma-Glutamylethylamide
• Suntheanine
• Teanina
• Theanine

What is this product used for?

L-Theanine may help as a sleep aid in some people. It may also help some people to relax.

What are the precautions when taking this product?

• Always check with your doctor before you use a natural product. Some products may not mix well with other drugs or natural products.

• Be sure to tell your doctor if you are pregnant, plan on getting pregnant, or are breastfeeding. You will need to talk about the benefits and risks of using this natural product.

• Avoid beer, wine, and mixed drinks (alcohol) while taking this product.

• This product may cause you to be sleepy. Take extra care driving and doing tasks that you need to be alert for.

• Take extra care and check with your doctor if you have:

  • Anxiety

  • Low mood or depression

  • Blood pressure problems

What should I watch for?

• Upset stomach

• Feeling dizzy

Related/similar drugs

When do I need to call the doctor?

• Signs of a very bad reaction. These include wheezing; chest tightness; trouble breathing, swallowing, or talking; fever; rash; hives; itching, discolored, swollen, blistered, or peeling skin; or swelling of face, lips, tongue, or throat. Go to the ER right away.

• Signs of low blood pressure. These include feeling dizzy, weak, or tired; fainting; more thirst; or skin that is pale, cool, and clammy.

• Very bad headache

• Very bad throwing up

Last Reviewed Date

2023-06-12

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