Night Sweats

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Medical Author: Melissa Conrad Stoppler, MD
Medical Editor: William C. Shiel, Jr, MD, FACP, FACR

• Introduction
• What are the causes of night sweats?
• Menopause
• Idiopathic hyperhidrosis
• Infections
• Cancer
• Medications
• Hypoglycemia
• Hormone Disorders
• Neurologic conditions
• Patient Discussions: Night Sweats - Describe Your Experience

Introduction

Doctors in primary care fields of medicine often hear their patients complain of night sweats as they are common. Night sweats refer to any excess sweating occurring during the night. However, if your bedroom is unusually hot or you are using too many bedclothes, you may begin to sweat during sleep - and this is normal. In order to distinguish night sweats that arise from medical causes from those that occur because one's surroundings are too warm, doctors generally refer to true night sweats as severe hot flashes occurring at night that can drench sleepwear and sheets, which are not related to an overheated environment.

In one study of 2267 patients visiting a primary care physician, 41% reported experiencing night sweats during the previous month, so the perception of excessive sweating at night is fairly common. It is important to note that flushing (a warmth and redness of the face or trunk) may also be hard to distinguish from true night sweats.

What are the causes of night sweats?

There are many different causes of night sweats. To determine what is causing night sweats in a particular patient, a doctor must obtain a detailed medical history and order tests to decide if an underlying medical condition is responsible for the night sweats.

The following are some of the known conditions that can cause night sweats.

Menopause

The hot flashes that accompany the menopausal transition can occur at night and cause sweating. This is a very common cause of night sweats in perimenopausal women. It is important to remember that hot flashes and other symptoms of the perimenopause can precede the actual menopause (the cessation of menstrual periods) by several years.

Night Sweats - Describe Your Experience

The MedicineNet physician editors ask:

Please describe your experience with night sweats.

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