lemborexant

Lemborexant is a prescription medication approved for the treatment of insomnia in adults, including difficulties with sleep onset and/or sleep maintenance. It is a dual orexin receptor antagonist (DORA) that was developed by Eisai and is marketed in the United States under the brand name Dayvigo.

Mechanism of action

Lemborexant binds to and blocks orexin receptors OX1 and OX2 in the central nervous system. By inhibiting orexin signaling, it reduces wake-promoting activity and facilitates the onset and maintenance of sleep.

Indications and usage

The drug is indicated for adults with insomnia characterized by difficulties with sleep initiation and/or sleep maintenance. It is intended for nightly use prior to going to bed when a full night’s sleep (typically seven hours or more) is anticipated.

Administration and dosing considerations

Lemborexant is taken orally once nightly before bedtime. Patients should avoid alcohol and be mindful of potential next-day impairment. Onset of sleep is typically within about an hour, but individual response varies.

Pharmacokinetics and interactions

Lemborexant is metabolized mainly by the cytochrome P450 3A (CYP3A) enzymes. Strong CYP3A inhibitors or inducers can significantly affect its exposure, necessitating dose adjustments or avoidance of concurrent use. Moderate inhibitors may require adjustments, while inducers can reduce effectiveness.

Safety and adverse effects

Common adverse effects include somnolence, dizziness, fatigue, headache, and abnormal dreams. There is a risk of next-day impairment and, in rare cases, complex sleep-related behaviors (such as sleep-driving or other activities performed while not fully awake). Caution is advised in populations susceptible to sedation and in those with hepatic impairment.

History

FDA approval for adults was granted in 2019, and the medication represents a non-GABAergic option for treating chronic insomnia.