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Tasimelteon

Generic Name: tasimelteon (TAS i MEL tee on)
Brand Name: Hetlioz

Medically reviewed by Drugs.com on Nov 4, 2019 – Written by Cerner Multum

What is tasimelteon?

Tasimelteon is a sedative, also called a hypnotic. It works by affecting certain substances in your body that help regulate your "sleep-wake cycle."

Tasimelteon is used to treat non-24-hour sleep-wake disorder.

Tasimelteon may also be used for purposes not listed in this medication guide.

Important Information

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

Before taking this medicine

Tell your doctor if you have ever had:

Tell your doctor if you are pregnant or breastfeeding.

Tasimelteon is not approved for use by anyone younger than 18 years old.

How should I take tasimelteon?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Take the medicine before your normal bedtime, at the same time each night.

Swallow the capsule whole and do not crush, chew, break, or open it.

Take tasimelteon without food.

After you take tasimelteon, avoid doing anything other than getting ready for bed.

It may take several weeks or months before your symptoms improve. Keep using the medication as directed and tell your doctor if your symptoms do not improve.

Store at room temperature away from moisture, heat, and light.

What happens if I miss a dose?

Tasimelteon should be taken only at your normal bedtime. Skip any missed dose. Do not use two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking tasimelteon?

Avoid driving or hazardous activity until you know how tasimelteon will affect you. Your reactions could be impaired.

Drinking alcohol may increase drowsiness caused by tasimelteon.

Tasimelteon side effects

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

Call your doctor at once if you have:

  • pain or burning when you urinate.

Side effects may be more likely in older adults.

Common side effects may include:

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.

Tasimelteon dosing information

Usual Adult Dose for Insomnia:

20 mg orally once per day

Comments:
-Take before bedtime, at the same time every night.
-Take without food.

Use: Treatment of Non-24-Hour Sleep-Wake Disorder (Non-24)

What other drugs will affect tasimelteon?

Using tasimelteon with other drugs that make you drowsy can worsen this effect. Ask your doctor before using opioid medication, a sleeping pill, a muscle relaxer, or medicine for anxiety or seizures.

Sometimes it is not safe to use certain medications at the same time. Some drugs can affect your blood levels of other drugs you take, which may increase side effects or make the medications less effective.

Other drugs may affect tasimelteon, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.