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Hetlioz

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

Medically reviewed by Judith Stewart, BPharm. Last updated on Jan 14, 2021.

What is Hetlioz?

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

Hetlioz is used to treat non-24-hour sleep-wake disorder in adults.

Hetlioz is also used to treat nighttime sleep problems in people with a genetic disorder called Smith-Magenis Syndrome (SMS). The capsule form of Hetlioz is for people with SMS who are at least 16 years old. The oral suspension (liquid) form is for children with SMS who are from 3 to 15 years old.

Warnings

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

You should not use Hetlioz if you are allergic to tasimelteon.

To make sure Hetlioz is safe for you, tell your doctor if you have ever had:

Tell your doctor if you are pregnant or breastfeeding.

Do not give this medicine to a child without medical advice. Hetlioz is approved to treat nighttime sleep problems only in children who have SMS and are at least 3 years old. Hetlioz is not approved to treat non-24-hour sleep-wake disorder in anyone younger than 18 years old.

How should I take Hetlioz?

Take Hetlioz exactly as your health care provider tells you. Follow all directions on your prescription label and read all medication guides or instruction sheets.

Take the medicine 1 hour before your normal bedtime, at the same time each night.

Take Hetlioz without food.

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

Only Hetlioz capsules should be used in people 16 years and older. Hetlioz oral suspension is for use only in children who are 3 to 15 years old.

Shake the oral suspension for at least 30 seconds before you measure a dose. Use the dosing syringe provided, or use a medicine dose-measuring device (not a kitchen spoon).

Read and carefully follow the Instructions for Use provided with the oral suspension syringe and press-in bottle adapter. Ask your doctor or pharmacist if you do not understand these instructions.

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

Tasimelteon doses are based on weight in children. Your child's dose needs may change if the child gains or loses weight.

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

Store the liquid medicine in the refrigerator. Throw away any leftover liquid 5 weeks after opening the 48-milliliter bottle, or 8 weeks after opening the 158-milliliter bottle.

Dosing information

Usual Adult Dose for Non-24-Hour Sleep-Wake Disorder:

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)

Usual Adult Dose for SMS Sleep Disturbances:

20 mg orally once per day

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

Use: Treatment of SMS Sleep Disturbances in patients 16 years of age and older

Usual Pediatric Dose for SMS Sleep Disturbances:

20 mg orally once per day in patients weighing over 28 kg
0.7 mg/kg orally once per day in patients weighing 28 kg or less

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

Use: Treatment of SMS Sleep Disturbances in patients 3 to 15 years of age

What happens if I miss a dose?

Hetlioz 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 to avoid

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

Drinking alcohol may increase drowsiness caused by tasimelteon.

Hetlioz side effects

Get emergency medical help if you have signs of an allergic reaction to Hetlioz: 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 Hetlioz 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.

What other drugs will affect Hetlioz?

Using Hetlioz 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 interact with 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 Hetlioz only for the indication prescribed.

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