What is Hetlioz: Uses, Warnings & Interactions

Updated May 14, 2025  •  Published Dec 30, 2020

Hetlioz overview

BRAND NAMES:

  • Hetlioz

Generic Names:

  • Hetlioz

Uses:

  • Treats non-24-hour sleep-wake disorder (non-24).

Therapeutic Classes:

  • Central Nervous System Agent

Forms:

  • Capsule

How it’s taken:

  • By mouth

What is Hetlioz used for?

Hetlioz comes in capsule form and is used as a treatment for Non-24-Hour sleep-wake disorder. It is a sedative that works by affecting certain substances in you body that help regulate your "sleep-wake" cycle. Hetlioz is not recommended for use in patients with severe liver problems. Common side effects may include headaches, abnormal dreams, elevate liver enzymes and urinary tract infection.

What form(s) does Hetlioz come in

  • Capsule

What are common Hetlioz doses?

  • Capsule 20MG

How to take Hetlioz

  • Your doctor will tell you how much medicine to use. Do not use more than directed. You may need to use it for several weeks or months before it begins to work for you.

  • Take this medicine at the same time every night before bedtime.

  • Oral routeIt is best to take this medicine on an empty stomach.

  • Swallow the capsule whole. Do not crush, break, or chew it.

  • Missed dose: If you cannot take this medicine at about the same time as usual on a given night, skip your dose. Take your regular dose as usual the next night. Do not take extra medicine to make up for a missed dose.

  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.

  • Take this medicine at the same time every night before bedtime.

  • Missed dose: If you cannot take this medicine at about the same time as usual on a given night, skip your dose. Take your regular dose as usual the next night. Do not take extra medicine to make up for a missed dose.

  • Your doctor will tell you how much medicine to use. Do not use more than directed. You may need to use it for several weeks or months before it begins to work for you.

  • Swallow the capsule whole. Do not crush, break, or chew it.

  • Oral routeIt is best to take this medicine on an empty stomach.

  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.

What to do if you miss a dose of Hetlioz

Hetlioz contraindications

  • This medicine is generally considered safe for most people. Talk to your doctor if you have concerns.

Hetlioz warnings

  • Your doctor will check your progress and the effects of this medicine at regular visits. Keep all appointments.

  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

  • Tell your doctor if you are pregnant or breastfeeding, if you have kidney disease or liver disease, or if you smoke.

  • This medicine may cause some people to become drowsy, sleepy, or less alert than they are normally. It is best to limit your activity after you take this medicine.

Hetlioz interactions

  • Some foods and medicines can affect how tasimelteon works. Tell your doctor if you also use fluvoxamine or rifampin.

  • This medicine may cause some people to become drowsy, sleepy, or less alert than they are normally. It is best to limit your activity after you take this medicine.

  • Your doctor will check your progress and the effects of this medicine at regular visits. Keep all appointments.

  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

Hetlioz side effects

Serious Side Effects

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing

  • Change in how much or how often you urinate, difficult or painful urination

  • Nightmares or unusual dreams

Less Serious Side Effects

  • Headache

  • Cough, runny or stuffy nose, sore throat

  • Nightmares or unusual dreams

Subscribe to our savings newsletter

Health education, drug info, wellness & more

By clicking 'Subscribe', I agree to SingleCare's Terms & Conditions.