Generic drug: tasimelteon
Brand name: Hetlioz LQ
Hetlioz LQ (tasimelteon) is a melatonin receptor agonist used for the treatment of Non-24-Hour Sleep-Wake Disorder (Non-24).
What are the side effects of Hetlioz?
Common side effects of Hetlioz include:
- headache,
- elevated liver enzymes (alanine aminotransferase, or ALT) in the blood,
- nightmares or abnormal dreams,
- disturbed night’s sleep,
- drowsiness,
- upper respiratory tract infections, or
- urinary tract infections.
Somnolence
- After taking Hetlioz, patients should limit their activity to preparing for going to bed. Hetlioz can potentially impair the performance of activities requiring complete mental alertness.
Patient Counseling Information
- Patient should read the FDA-approved patient labeling for Hetlioz LQ oral suspension, if appropriate.
Does Hetlioz cause addiction or withdrawal symptoms?
Drug Abuse And Dependence
Controlled Substance
- Tasimelteon is not a controlled substance under the Controlled Substances Act.
Abuse
- Tasimelteon did not produce any abuse-related signals in animal behavioral studies. Rats did not self-administer tasimelteon, suggesting that the drug does not have rewarding properties. There were also no signs or symptoms indicative of abuse potential in clinical studies with Hetlioz.
Dependence
- Discontinuation of Hetlioz in humans following chronic administration did not produce withdrawal signs. Hetlioz does not appear to produce physical dependence.
What is the dosage for Hetlioz?
Non-Interchangeability Between Hetlioz Capsules And Hetlioz LQ Oral Suspension
- Hetlioz capsules and Hetlioz LQ oral suspension are not substitutable.
Recommended Dosage For Hetlioz Capsules forNon-24
Adults
- The recommended dosage of Hetlioz capsules in adults is 20 mg one hour before bedtime, at the same time every night.
- Because of individual differences in circadian rhythms, drug effect may not occur for weeks or months.
Recommended Dosage For Hetlioz Capsules And Hetlioz LQ Oral Suspension for Night time Sleep Disturbances In SMS
Patients 16 Years Of Age And Older
- The recommended dosage of Hetlioz capsules in patients 16 years and older is 20 mg one hour before bedtime, at the same time every night.
Pediatric Patients 3 Years To 15 Years Of Age
- The recommended dosage of Hetlioz LQ oral suspension in pediatric patients 3 years to 15 years of age is based on body weight (Table 1). Administer Hetlioz one hour before bedtime, at the same time every night.
Table 1: Recommended Dosage of HetliozLQ Oral Suspension for the Treatment of Nighttime Sleep Disturbances in SMS in Pediatric Patients 3 Years to 15 Years of Age
Body Weight | Daily Dose (oral suspension) |
≤28 kg | 0.7 mg/kg one hour before bedtime |
>28 kg | 20 mg one hour before bedtime |
Important Administration Information
- Administer Hetlioz capsules and Hetlioz LQ oral suspension without food.
- If a patient is unable to take Hetlioz at approximately the same time on a given night, they should skip that dose and take the next dose as scheduled.

QUESTION
Why do we sleep? See AnswerWhat drugs interact with Hetlioz?
Strong CYP1A2 Inhibitors (e.g., fluvoxamine)
- Avoid use of Hetlioz in combination with fluvoxamine or other strong CYP1A2 inhibitors because of a potentially large increase in tasimelteon exposure and greater risk of adverse reactions.
Strong CYP3A4 Inducers (e.g., rifampin)
- Avoid use of Hetlioz in combination with rifampin or other CYP3A4 inducers because of a potentially large decrease in tasimelteon exposure with reduced efficacy.
Beta-Adrenergic Receptor Antagonists(e.g., acebutolol,metoprolol)
- Beta-adrenergic receptor antagonists have been shown to reduce the production of melatonin via specific inhibition of beta-1 adrenergic receptors.
- Nighttime administration of betaadrenergic receptor antagonists may reduce the efficacy of Hetlioz.
Is Hetlioz safe to use while pregnant or breastfeeding?
- Available postmarketing case reports with Hetlioz use in pregnant women are not sufficient to evaluate drug-associated risk of major birth defects, miscarriage or adverse maternal or fetal outcomes.
- There are no data on the presence of tasimelteon or its metabolites in human or animal milk, the effects on the breastfed infant, or the effects on milk production.
- The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for Hetlioz and any potential adverse effects on the breastfed infant from Hetlioz or from the underlying maternal condition.
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Summary
Hetlioz LQ (tasimelteon) is a melatonin receptor agonist used for the treatment of Non-24-Hour Sleep-Wake Disorder (Non-24). Common side effects of Hetlioz include headache, elevated liver enzymes (alanine aminotransferase, or ALT) in the blood, nightmares or abnormal dreams, disturbed night’s sleep, drowsiness, upper respiratory tract infections, or urinary tract infections. Hetlioz can potentially impair the performance of activities requiring complete mental alertness.
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