Periwell
Category: VasomotorClinical Profile

Night Sweats

Waking drenched in sweat — often multiple times a night — disrupting sleep and leaving you exhausted, wrung out, and dreading bedtime.

Biological Mechanism

Night sweats are hot flashes that occur during sleep. The same hypothalamic thermostat disruption drives both — but nocturnal symptoms cause sleep fragmentation at a particularly damaging stage. REM sleep and slow-wave (deep) sleep are both disrupted by night sweats, which means women lose the most restorative phases of the sleep cycle. The resulting sleep deprivation creates a cascade: impaired cognitive function, worsened mood, increased cortisol, exacerbated anxiety, and paradoxically sometimes worsened hot flashes during the day.

Common Misdiagnoses

Primary insomnia, Sleep apnea (important to rule out — prevalence rises post-menopause), Lymphoma or other malignancy (drenching night sweats without hot flush quality), Infections (TB), Medication side effects (some antidepressants, tamoxifen)

Evidence-Based Treatments

  • 01Transdermal estradiol

    Directly addresses the hypothalamic mechanism. Most women experience significant improvement in 4–8 weeks. Most cost-effective intervention for sleep disruption in perimenopause.

  • 02Oral micronized progesterone at bedtime

    Sedative properties via allopregnanolone. Taken at night, typically produces earlier sleep onset and reduced nocturnal waking — independently of estrogen.

  • 03Sleep environment optimisation

    Cooling mattress toppers, moisture-wicking bedding, room temperature 16–18°C. Adjunctive — does not treat the mechanism.

  • 04Fezolinetant (Veozah)

    Non-hormonal NK3 receptor antagonist. Reduces nocturnal hot flash frequency and improves sleep quality measures.