Postmenopausal women who experience chronic insomnia may benefit from the dual orexin receptor antagonist suvorexant, a small US study suggests.

Researchers say the drug, which was well-tolerated among participants, could provide a novel therapeutic option for those with vasomotor symptom-associated insomnia.

In the randomised controlled trial, 56 middle-aged women with chronic insomnia associated with night-time vasomotor symptoms (VMS) were assigned to receive either 10-20mg oral suvorexant or placebo every night for four weeks.

Participants had an Insomnia Severity Index (ISI) score of at least 15 and at least 30 minutes of diary-rated wake after sleep-onset (WASO).