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Brands: Hetlioz, Hetlioz LQ
Published 2025-12-23 · Last reviewed 2025-12-30 · 4 references
Content sourced from FDA labeling (DailyMed) and peer-reviewed literature.
Tasimelteon is a melatonin receptor agonist indicated for treatment of Non-24-Hour Sleep-Wake Disorder (Non-24) in adults (label).
Non-24 is a circadian rhythm disorder. Clinical framing emphasizes circadian entrainment and consistency rather than immediate hypnotic sedation; drug effects may take weeks or months to emerge (label/clinical).
In pivotal phase 3 trials in totally blind adults with Non-24, tasimelteon increased circadian entrainment and improved clinical sleep measures versus placebo; ongoing nightly dosing was needed to sustain benefit (trial/clinical).
Tasimelteon is not a controlled substance and generally has low misuse potential, but next-day somnolence can occur and interaction management is clinically important (label/clinical).
Strong CYP1A2 inhibitors (e.g., fluvoxamine) and strong CYP3A4 inducers (e.g., rifampin) are avoided due to large exposure changes; smoking may reduce exposure via CYP1A2 induction (label).
The tasimelteon compare view, evidence feed, and print page support review of melatonin-pathway agents and alternative sleep strategies.
Tasimelteon is a niche but clinically important option for Non-24; real-world success depends on adherence to consistent timing, patience for delayed onset of circadian effects, and careful interaction management (label/clinical).
View labelExactRefer to the Glossary entry on Neurotransmitters for background on receptor systems involved in serious mental illness.
Dual melatonin receptor agonist (MT1/MT2). Clinical framing emphasizes shifting/entraining circadian timing rather than producing rapid sedative-hypnotic effects (label/clinical).
Because benefit can take weeks to months, follow-up often focuses on sleep timing and daytime function rather than short-term sleep latency alone (clinical).