Why do I sweat at night under my armpits?
You wake up to find your armpits, and sometimes your entire upper body, drenched, even though the room doesn't feel particularly warm. Night sweats can disrupt your sleep, and it quickly raises the question: is this normal, or is something else going on?
By Zero·One Redactie
2 July 2026
3 min. reading time
The most common causes
Your bedroom environment
A room that's too warm, thick blankets, or synthetic bedding are the most obvious, and most common, causes. Synthetic fabrics like polyester trap heat and moisture more than natural materials, causing your body temperature under the bedding to rise more than necessary.
A simple test: if the problem disappears as soon as you lower the room temperature or switch to cotton bedding, the cause is likely here.
Hormonal changes
In women between 40 and 60, night sweats are often a direct result of menopause, where fluctuating estrogen levels temporarily disrupt temperature regulation in the brain. We discuss this mechanism in detail in [Sweating during menopause: hot flashes and night sweats, and what helps].
But hormonal fluctuations don't only play a role during menopause: night sweats can also occur around the menstrual cycle, during pregnancy, or with hormonal disorders.
Stress and unresolved tension
Tension that you suppress during the day or don't fully process can manifest at night when your conscious control disappears during sleep. This explains why some people primarily experience night sweats during periods of busyness or uncertainty, even if they don't feel overtly stressed during the day.
Food and drinks before bed
Alcohol, caffeine, and spicy food right before bed can all contribute to a higher body temperature and more sweating during the night. Alcohol also dilates blood vessels, which gives a warm sensation that can last into your sleep.
Medication
Some medications, including certain antidepressants and painkillers, have night sweats as a known side effect. This is often stated in the leaflet.
One wipe. Up to five days dry.
Discrete anti-perspirant wipes, individually wrapped in a plastic-free sachet. Apply in the evening, ready for the next day.
Why does applying it in the evening actually make sense?
If your armpits sweat at night, it's natural to wonder when is the best time to apply an antiperspirant. The answer is: in the evening, and there's a good reason for it.
During the day, your skin is often already moist from previous activity, and clothing can affect product absorption. In the evening, on clean and completely dry skin, an antiperspirant can be absorbed optimally, without the disruption of clothing or daily activity. The night also gives the formula time to work fully while your sweat glands are at rest.
This means that an evening application not only protects the next day but can also directly relieve night sweats in the armpits themselves, as the protection is already active while you sleep.
Zero·One antiperspirant wipes are designed for this: dab onto clean, dry skin before bed, let dry for five minutes, and wash off the next morning. The protection continues to work, both at night and during the day, for up to five days per wipe.
What else can you do?
In addition to a targeted antiperspirant, a few practical adjustments can help:
Keep your bedroom cool, ideally between 16 and 19 degrees Celsius. Choose cotton or linen bedding and nightwear instead of synthetic fabrics. Avoid alcohol, caffeine, and heavy, spicy meals right before bed. Consider a fan or leaving a window ajar if your room heats up quickly.
When is it time to talk to a doctor?
If night sweats suddenly start without a clear cause, are accompanied by weight loss, persistent fever, or severely disrupt your sleep despite adjustments to your sleeping environment, it's wise to discuss this with your doctor. You can read more about when to take these signs seriously in [Sweating a lot for no reason? When it's normal and when to see a doctor].
Frequently asked questions
Is night sweating in my armpits different from night sweating all over my body? Yes, localized night sweating in the armpits often points to a local factor, such as clothing or a specific antiperspirant need, while night sweating all over the body is more often associated with hormonal or systemic causes.
Does showering in the evening before bed help? It can help your skin start the night clean and cool, and it's also the ideal time to apply an evening antiperspirant to clean skin.
Can my mattress be the cause of night sweats? A mattress without good ventilation, for example certain types of memory foam, can retain heat and contribute to a higher sleeping temperature.
Is night sweating in the armpits a sign of menopause? It can be one of the signs, especially in women between 40 and 60, but it can also have other causes such as room temperature, diet, or stress.
Does an antiperspirant applied in the evening also work against night sweats themselves? It reduces sweat production in the treated area, such as the armpits, during the night. It does not change the underlying cause if it is hormonal or environmental, but it does limit the physical consequences.
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