Night Sweats: Common Causes, What to Track and When to Be Seen

What it involves

MedlinePlus explains that sweating is the release of salty liquid from the sweat glands and is the body's natural way of regulating temperature. It is controlled by the part of the nervous system that is not under your control, and a number of everyday and medical causes can make it heavier.

Who this is for

• Patients who wake soaked several nights a week without an obvious reason such as a warm room
• Patients whose sweating comes with fever, weight loss, a rapid heartbeat or chest discomfort
• Patients who started a new medicine and noticed more sweating afterward
• Patients around the age of menopause who want to know whether hot flashes could be the cause

What to expect

• Questions about how often it happens, whether it also occurs in the daytime and what else you have noticed
• A review of your medicines, alcohol and caffeine use, and any recent illness
• A physical exam, and blood work if the history suggests it, since the practice lists blood work among its services
• A follow-up plan, including referral if the cause points beyond primary care

Start with the room, then look further

MedlinePlus lists hot weather and warm temperatures among the first things that make you sweat more, along with exercise and situations that make you nervous, angry, embarrassed or afraid. In a warm bedroom, heavy bedding or pajamas are a simple explanation. The question that separates ordinary sweating from something worth a visit is whether the sweating is out of proportion to the conditions. If you wake up soaked in a cool room, with light bedding, repeatedly, that is the pattern to describe to a provider.

Causes on MedlinePlus's list

MedlinePlus names alcohol and caffeine, anxiety and stressful situations, fever, infection and menopause, which it says can bring heavy sweating as hot flashes. Spicy foods can trigger it in some people. Some medicines can increase sweating too, and it gives thyroid hormone, morphine, medicines to reduce fever and medicines that treat mental disorders as examples. Low blood sugar, withdrawal from alcohol, sedatives or narcotic painkillers, and cancer also appear. That list is long, which is why the history carries so much weight.

Where a sleep-time pattern points

Sweating that occurs at night does not by itself prove any one cause, but it narrows the questions. A person who also notices a pounding heart may need their thyroid considered, and the thyroid care page describes how that is followed. Someone with a fever or recurring infection would be asked different questions, covered in the fever guide. Shakiness and hunger that wake you can suggest low blood sugar, and the low blood sugar guide explains that pattern.

Signs that make a visit more urgent

MedlinePlus says to contact a provider if sweating comes with chest pain, fever, a rapid and pounding heartbeat, shortness of breath or weight loss, because these symptoms may point to a problem such as an overactive thyroid or an infection. It also advises contact if you sweat a lot or for a long time without explanation, if sweating comes with chest pain or pressure, or if you lose weight or often sweat during sleep. Chest pain with sweating is not something to book a routine appointment for. Call 911 in that case.

What to track before you come in

A week or two of simple notes makes the visit more useful. Jot down how many nights you woke sweating, what time, how warm the room was, whether you had alcohol or caffeine late in the day, and any fever or weight change you noticed. Bring a list of every medicine and supplement, including over-the-counter ones, since new or changed doses can line up with the onset of sweating. If you are of an age where menopause is possible, note changes in periods or hot flashes during the day as well.

Easing it while you wait

MedlinePlus advises drinking plenty of fluids after heavy sweating, including water or fluids with electrolytes such as sports drinks, to replace what was lost. It also suggests lowering the room temperature a little to prevent more sweating, and washing the face and body if the salt from sweat has dried on the skin. Changing damp sheets and nightclothes helps you get back to sleep. These steps are comfort measures. They do not replace finding the cause when the sweating keeps returning.

Sources

• MedlinePlus — Sweating