(trade name)


Therapeutic: sedative hypnotics
Pharmacologic: melatonin receptor agonists
Pregnancy Category: C


Treatment of non-24–Hour Sleep-Wake Disorder (a circadian rhythm disorder more common in totally blind patients).


Acts as an agonist at melatonin MT1 and MT2 receptor sites, which are involved in regulation or circadian rhythm.

Therapeutic effects

Improved circadian rhythm with improved sleep/wake patterns.


Absorption: Systemic absorption follows oral administration, blood levels are ↑ in female patients.
Distribution: Unknown.
Metabolism and Excretion: Extensively metabolized mostly by CYP1A2 and also CYP3A4, metabolited do not contribute significantly to pharmacological effect. Metabolites are primarily excreted in urine, less than 1% as unchanged drug), 4% excreted in feces.
Half-life: 1.3 hr.

Time/action profile (establishment of circadian rhythm/sleep cycle)



Contraindicated in: Severe hepatic impairment.
Use Cautiously in: Concurrent use of strong inducers/inhibitors of CYP1A2 (may alter drug effects); Geriatric: ↑ risk of adverse reactions in patients > 65 yr (↑ blood levels); Obstetric: May cause fetal harm, use only if potential benefit justifies potential fetal risk; Lactation: use cautiously if breastfeeding;Safe and effective use in children has not been established.

Adverse Reactions/Side Effects

Central nervous system

  • headache
  • nightmares/unusual dreams


  • ↑ liver enzymes


Drug-Drug interaction

Concurrent use of strong inhibitors of CYP1A2 including fluvoxamine may ↑ drug effects).Concurrent use of strong inducersof CYP1A2 including rifampin and cigarette smoke may ↓ drug effects.Strong inhibitors of CYP3A4, including ketoconazole may ↑ blood levels and effects.Alcohol may ↑ CNS depression.


Oral (Adults) 20 mg at bedtime, taken at the same time every day.


Capsules: 20 mg

Nursing implications

Nursing assessment

  • Assess mental status, sleep patterns, and frequency of daytime naps prior and periodically during therapy.
  • Lab Test Considerations: May cause ↑ transaminases.

Potential Nursing Diagnoses

Readiness for enhanced sleep (Indications)


  • Oral: Administer without food before bedtime at the same time each night. Swallow capsule whole; do not open, dissolve, crush, or chew.

Patient/Family Teaching

  • Instruct patient to take tasimelteon as directed at the same time each day. If unable to take at approximately the same time on a given night, skip dose and resume following night. After taking, advise patient to limit activity to preparing to go to bed.
  • Caution patient tasimelteon can impair performance of activities requiring complete mental alertness. Advise patient to avoid driving and other activities requiring alertness after taking tasimelteon.
  • Advise female patient to notify health care professional if pregnancy is planned or suspected or if breastfeeding

Evaluation/Desired Outcomes

  • Improved circadian rhythm with improved sleep/wake patterns. Due to differences in circadian rhythms, may require daily use for several wks or mo before benefit from tasimelteon is noticeable.
Drug Guide, © 2015 Farlex and Partners
References in periodicals archive ?
Food and Drug Administration (FDA) as part of its ongoing review of Vanda's supplemental New Drug Application (sNDA) for HETLIOZ (tasimelteon) for the treatment of Jet Lag Disorder (JLD).
Vanda Pharmaceuticals Inc (Nasdaq:VNDA) said on Thursday that it has submitted its Supplemental New Drug Application for HETLIOZ (tasimelteon) with the US Food and Drug Administration (FDA) for the treatment of jet lag disorder.
BALTIMORE -- Tasimelteon, a drug approved for non-24-hour sleep-wake disorder, has been shown to increase sleep times in travelers with jet lag, according to results from a phase 3 trial.
In January 2014, the US Food and Drug Administration (FDA) approved Hetlioz (tasimelteon), a melatonin receptor agonist, for the treatment of non-24.
"Melatonin receptor agonists" (analogues of melatonin designed to bind to melatonin receptors with a greater potency than melatonin itself), such as the drug tasimelteon, have been investigated in the treatment of circadian rhythm disorders.
Suvorexant (Belsomra) and tasimelteon (Hetlioz) are oral drugs given for the treatment of insomnia and the treatment of non-24-hour sleep-wake disorder, respectively.
Suvorexant (Belsomra) and tasimelteon (Hetlioz) are oral drugs given for treatment of insomnia and the treatment of non-24-hour sleep-wake disorder, respectively.
An exception is two melatonin antagonists, approved by the Food and Drug Administration, Rozerem and Tasimelteon, strictly used for insomnia (23, 24, 25).
Tasimelteon, also a selective MT1 and MT2 agonist, is undergoing phase III trials for insomnia (36) and agomelatine, an MT1/MT2 agonist and 5HT2c antagonist, is being evaluated as an antidepressant/anxiolytic drug (37).
'Tasimelteon' works by shifting the natural ebb and flow of the body's sleep hormone melatonin and resetting the body's natural sleep rhythms.
Two company-funded studies found people who went to bed five hours earlier than normal fell asleep faster and spent less time tossing and turning when given tasimelteon rather than a placebo.