Belsomra for Menopause Insomnia: What a Trial in Women With Hot Flashes Found

What is Belsomra, and how does it work?

Belsomra is the brand name for suvorexant, a prescription medicine for insomnia. It belongs to a class called orexin receptor antagonists. Orexin A and orexin B are brain chemicals that help keep you awake; Belsomra blocks the receptors they act on, which is thought to quiet the brain's drive to stay awake. It's a Schedule IV controlled substance.

That makes it different from older sleeping pills such as Ambien, which work by boosting GABA, the brain's main calming signal. Rather than sedating the whole system, the idea behind Belsomra is to switch off one of the signals that keeps it running.

The label approves Belsomra for insomnia with difficulty falling asleep and/or staying asleep. That second part matters in midlife, when the classic complaint is waking at 2 or 3 a.m. and not getting back to sleep, rather than lying awake at bedtime.

Why test Belsomra for menopause insomnia?

Researchers tested Belsomra in midlife women because orexin seems to be involved in both wakefulness and body temperature control. The authors of the 2022 trial described orexin as promoting wakefulness, helping regulate temperature, rising after menopause and returning to normal in women given estrogen. That is their reasoning for the trial, not proof of how it works.

If that theory is right, blocking orexin might help with both the waking and the night-time hot flashes behind it. A 2025 review in CNS Spectrums looked at the same question across animal, laboratory and human studies and treated it as a promising possibility rather than an established fact.

What did the trial in midlife women find?

The trial, published in the journal Sleep in 2022, enrolled 56 midlife women with chronic insomnia linked to night-time hot flashes. Each had a moderate-or-worse score on the Insomnia Severity Index and spent more than 30 minutes awake during the night. They took suvorexant 10 to 20 mg (27 women) or a placebo (29 women) every night for four weeks.

Not every result was positive. Diary-rated time awake during the night and total sleep time trended in the right direction on suvorexant, but the differences weren't significant once the researchers adjusted for testing many outcomes. Daytime hot flashes and other sleep measures didn't differ between the groups. The authors reported that suvorexant was well tolerated.

This is one small trial, four weeks long, mostly using diaries rather than sleep-lab recordings, and I could read only its summary. It's encouraging, but it isn't enough to call Belsomra a proven menopause treatment, and the FDA hasn't approved it for hot flashes.

How well does Belsomra work in general?

In the two 3-month trials behind its approval, Belsomra mainly helped people stay asleep. Measured in a sleep lab, people on suvorexant spent 17 to 31 fewer minutes awake during the night than those on placebo, and they estimated 11 to 22 more minutes of total sleep. Its effect on falling asleep was smaller and less consistent.

Those trials included many midlife women: the non-elderly group averaged 46 years old and was mostly female (465 women, 275 men). The label says efficacy was similar in women and men. They used 20 mg in younger adults and 15 mg in older ones, higher than today's recommended 10 mg starting dose.

The American Academy of Sleep Medicine's 2017 guideline suggests suvorexant for difficulty staying asleep only. That is a weak recommendation, and it rated the quality of the evidence as low. It found a clinically significant reduction in time awake during the night, but improvements in total sleep that fell short of clinical significance.

How should Belsomra be taken?

The label's recommended dose is 10 mg, taken no more than once a night, within 30 minutes of going to bed, with at least 7 hours left before you plan to wake. If 10 mg is tolerated but doesn't work, it can be raised to a maximum of 20 mg. A meal just before can delay its effect.

Women have somewhat higher exposure than men. The label reports total exposure about 17% higher in women after a 40 mg dose, and 46% higher in obese women than in non-obese women. It says that, particularly in obese women, the increased risk of side effects should be considered before raising the dose.

Some medicines change the dose too. With moderate CYP3A inhibitors, a group the label says includes grapefruit juice, fluconazole, diltiazem, verapamil, erythromycin and ciprofloxacin, the recommended dose is 5 mg, and generally no more than 10 mg. Strong inhibitors such as ketoconazole and clarithromycin aren't recommended with Belsomra at all.

What are the side effects of Belsomra?

The most common side effect of Belsomra is drowsiness. In the 3-month trials, it affected 7% of people on Belsomra versus 3% on placebo, and it was more common in women (8%) than men (3%). The label also says headache, abnormal dreams, dry mouth, cough and upper respiratory infections occurred at least twice as often in women as in men.

Fewer people stopped Belsomra because of side effects than stopped placebo: 3% versus 5%. Drowsiness rose with the dose, from 2% at 10 mg to 5% at 20 mg in a separate month-long study. That study also found a small dose-related rise in cholesterol of 1 to 2 mg/dL at 10 to 20 mg, compared with a 4 mg/dL fall on placebo.

What unusual side effects should you know about?

Some of Belsomra's warnings come from how it works. Blocking orexin can cause symptoms that resemble narcolepsy, a disorder of sudden sleep attacks: sleep paralysis, vivid dream-like hallucinations while falling asleep or waking, and brief leg weakness. The leg-weakness risk rises with the dose, and people with narcolepsy must not use it.

• Sleep paralysis: being unable to move or speak for up to several minutes as you fall asleep or wake up.
• Hallucinations: vivid and sometimes disturbing perceptions at those same moments, which our vivid dreams and nightmares article explores in a menopause context.
• Leg weakness: periods lasting from seconds to a few minutes, day or night, without an obvious trigger.
• Complex sleep behaviors: sleep-walking, sleep-driving and other activities while not fully awake can occur. The label says to stop Belsomra immediately if they do.
• Mood: trials showed a dose-related increase in suicidal thoughts on questionnaires. Any new low mood or change in behavior needs prompt attention.

Can Belsomra affect driving the next day?

Belsomra can affect driving the next day. Tested 9 hours after a dose, 20 mg caused clinically meaningful impairment in some non-elderly adults, and four women on Belsomra (20 or 40 mg) stopped their driving tests early because they felt too sleepy. The label says people on 20 mg should avoid next-day driving and other activities that need full alertness.

It also warns people on lower doses that sensitivity varies, that impairment can happen without feeling sleepy, and that effects may persist for several days after stopping. The label gives a mean half-life of about 12 hours, much longer than Ambien's roughly 2.5 hours, which helps explain why a full night matters. Alcohol adds to the impairment.

How does Belsomra compare with Ambien?

Belsomra and Ambien are both Schedule IV prescription sleep medicines, but they differ in how they work, what they're approved for and how their warnings are framed. Neither has been directly compared with the other in a trial in midlife women, so the table below compares their labels, not their results.

On dependence, Belsomra's label reports no physical dependence or withdrawal symptoms in completed trials. Its abuse potential isn't zero, though: in a study of recreational drug users, high doses of suvorexant produced "drug liking" ratings similar to zolpidem's.

Who should be careful with Belsomra?

People with narcolepsy shouldn't take Belsomra at all, according to its label. Extra caution applies to anyone with breathing problems, depression or past drug or alcohol misuse, or taking interacting medicines. It isn't recommended in severe liver disease. The label recommends re-evaluation if insomnia hasn't improved after 7 to 10 days.

• Sleep apnea: Belsomra hasn't been studied in severe obstructive sleep apnea. In a small study of mild to moderate apnea, 40 mg slightly raised the number of breathing pauses, and the label says meaningful effects can't be ruled out. Sleep apnea becomes more common after menopause, as our sleep apnea article explains.
• Other medicines: other sleep medicines aren't recommended alongside it, and digoxin levels may need monitoring.
• Breastfeeding: small amounts pass into breast milk, and there's no data on effects in breastfed infants.
• Older adults: the label found no meaningful differences in safety or effectiveness after 65 but notes a higher risk of falls from drowsiness. The 2023 Beers Criteria don't list suvorexant among drugs to avoid.

What do sleep doctors recommend first?

Sleep doctors recommend a non-drug treatment first. The 2017 American Academy of Sleep Medicine guideline says that all patients with chronic insomnia should receive cognitive behavioral therapy for insomnia (CBT-I) as a primary treatment. A 2026 pilot trial in midlife women with night-time hot flashes found a version adapted for menopause reduced insomnia severity.

If hot flashes are what wake you, treating them directly may also help sleep; our hot flashes guide and HRT for menopause insomnia cover the options. If you and your doctor decide a sleep medicine makes sense, our sleeping pills for menopause insomnia article compares the choices.

Where to go from here

To compare Belsomra with the most familiar sleeping pill, read Ambien for menopause insomnia. For non-drug approaches, start with our CBT-I guide and how to fall back asleep at 3 a.m. For other medicines, see trazodone and gabapentin.

For how all of this fits into the bigger picture of midlife sleep, start at the complete perimenopause and menopause sleep guide.

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