Why Do I Sweat so Much When I Sleep?

Sleeping Man
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A couple decades ago (we’re guessing), you learned to stop wetting the bed. Now your brain wakes you up whenever you’ve got to go, so…you get up and go.

But there’s another bed-soiling phenomenon that doesn’t go away. It’s significantly less humiliating, but equally annoying: Night sweats.

If you’re a victim of night sweats, you know that few things that happen in bed are less convenient—or more awkward, depending on the circumstances—than waking from a deep slumber and finding yourself in a pool of your own sweat. You move to another spot on the bed, or sleep on top of the sheets—just to wake up an hour or two later in another fever-like sweat.

And if you’re with a partner, it’s a thousand times worse.

Night sweats can be a side effect of a serious problem, the byproduct of a momentary illness, and even a visible sign of stress. It can also be the result of conditions in your environment—a hot room, a clingy partner—in which case it’s probably avoidable with just a few simple adjustments to your environment.

So if you suffer from night sweats—and if you do, you know that “suffer” is the word for it—answer these three questions from dermatologist Lindsey Bordone, M.D., of Columbia University Medical Center, and you’ll be on the road to understanding the problem and deciding how to deal with it.

1. Have you been sweating excessively for a while, and not just at night?

You may have a condition called hyperhidrosis, which is characterized by constant perspiration for no apparent reason, and is usually brought on by hormonal changes during puberty, says Bordone. In this case, you should probably speak with your dermatologist, who can administer treatments to help alleviate your symptoms.

2. Has your sweating come on suddenly as an adult, accompanied by other symptoms?

For example, has a sudden onset of night sweats been accompanied by rapid weight loss or other autoimmune conditions? It could be something manageable, says Bordone, like an acute infection or an episode of severe anxiety. Or, in rarer cases, it could be something more serious, like leukemia, lymphoma, or HIV. Don’t stress, but do see an internal medicine doctor for a screening and diagnosis.

Night sweats can also be caused by sleep apnea, an overactive thyroid, or an acute infection, Bordone adds—the first two appear more consistently over time, the latter in a quick wave. Some oral medications—like insulin or other diabetes meds, for example—can cause nighttime sweats as well, due to lowered blood sugar levels (aka hypoglycemia). Again, see your doctor to find out.

3. Are you sweating specifically—and routinely—at night, with no other symptoms?

In that case, it may be your environment that’s the culprit. Here, a few steps to take to resolve the problem:

*Lower the room temperature (and peel off the layers): As calming as it is to curl into a cocoon under your covers and drift off to sleep, it doesn’t do your body any favors in the “staying cool and dry” department. If you aren’t staying ventilated in a room that’s toasty or humid—then your body begins to sweat to cool off.

So try to sleep with the thermostat at around 67°, and get used to stripping down to your skivvies. This should create an optimal sleeping environment; it might even allow you to sleep next to your partner without overheating, as shared body temperature is one of the biggest causes of nighttime sweating.

*Drink less caffeine, and drink it earlier: If you’re chugging too many coffees, teas, or Red Bulls—especially late in the day—your increased heart rate won’t only make it difficult to fall asleep, it’ll also send your body into sweat overdrive once you do drift off.

*Ditch the drugs: The same goes for recreational drug use. Drugs like Ecstasy can spike the heart rate and lead to profuse sweating. You’ll wake in a pool of sweat, completely dehydrated. Now where’s the fun in that?

And significant hormonal shifts can cause you to wake in a sea sweat as well—so, careful with the mass-building hormones, brother.

Note: One thing you don’t have to worry about exacerbating night sweats: late workouts. “Generally, if you’ve cooled down from your workout and showered,” Bordone says, “then your heart rate and metabolism should return to baseline before bed. And the more well-conditioned the athlete, the faster his or her body returns to that baseline rate.”

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