Night Sweats in Adults: What They Could Mean and When to See a Doctor

What counts as a true night sweat?

Feeling warm and kicking off the blanket is not the same thing. A true night sweat means waking soaked — enough to need to change your clothes or sheets — despite your bedroom not being unusually hot. That distinction matters because it is what clinicians use to separate a physiological quirk from a symptom worth investigating.

What are the most common reasons adults wake up soaked?

Hormonal changes top the list. In people going through menopause, the drop in estrogen disrupts temperature regulation, producing hot flashes and soaking sweats 1Ref 1Faubion SS, Crandall CJ, Davis L, El Khoudary SR, Hodis HN, Lobo RA, Maki PM, Manson JE, Pinkerton JV, Santoro NF, Shifren JL, Shufelt CL, Thurston RC, Wolfman W (2022).The 2022 Hormone Therapy Position Statement of The North American Menopause Society.Menopause-related vasomotor symptoms (night sweats, hot flashes) and hormone therapy as a management option. A similar — often underappreciated — process happens in men as testosterone gradually declines 2Ref 2Mulhall JP, Trost LW, Brannigan RE, Kurtz EG, Redmon JB, Chiles KA, Lightner DJ, Miner MM, Murad MH, Nelson CJ, Platz EA, Ramanathan LV, Lewis RW (2018).Evaluation and Management of Testosterone Deficiency: AUA Guideline.Testosterone deficiency in men (andropause/late-onset hypogonadism) as an underappreciated cause of night sweats.

Anxiety and stress activate the same sweat response through the nervous system, which is why night sweats often track with periods of high stress or anxiety disorders 3Ref 3DeGeorge KC, Grover M, Streeter GS (2022).Generalized Anxiety Disorder and Panic Disorder in Adults.Anxiety and autonomic nervous system activation as a cause of night sweats.

Medications are a very common and frequently overlooked cause. Antidepressants (especially SSRIs and SNRIs), blood pressure medications, hormonal therapies, and some pain relievers can trigger sweating as a side effect. Night sweats that started or worsened after a new medication are worth flagging to your prescriber — never stop a medication without discussing it first.

Alcohol in the evening reliably raises core body temperature and dilates blood vessels, triggering sweating. Spicy food has a similar effect for many people.

What medical conditions can cause night sweats?

Infections — particularly tuberculosis, HIV, and certain fungal infections — have long been linked to drenching night sweats 4Ref 4US Preventive Services Task Force; Owens DK, Davidson KW, Krist AH, et al. (2019).Screening for HIV Infection: US Preventive Services Task Force Recommendation Statement.HIV as a cause of night sweats and the recommendation to screen when etiology is unclear. Clinicians ask about travel, exposures, and immune health when this is a possibility.

Hyperthyroidism (overactive thyroid) revs metabolism and can produce heat and sweating around the clock 5Ref 5Jonklaas J, Bianco AC, Bauer AJ, et al. (2014).Guidelines for the Treatment of Hypothyroidism: Prepared by the American Thyroid Association Task Force on Thyroid Hormone Replacement.Thyroid function tests as part of night sweats workup; hyperthyroidism as a cause of sweating and metabolic acceleration. Associated symptoms include unexplained weight loss, a rapid heartbeat, anxiety, and tremor.

Blood sugar swings — including nocturnal hypoglycemia in people on diabetes medications — can cause sweating at night 6Ref 6American Diabetes Association Professional Practice Committee (2024).Standards of Care in Diabetes—2024.Nocturnal hypoglycemia in people on diabetes medications as a cause of night sweats; blood glucose testing in the workup.

Obstructive sleep apnea — repeated breathing pauses during sleep — can also trigger sweating episodes 7Ref 7Kapur VK, Auckley DH, Chowdhuri S, et al. (2017).Clinical Practice Guideline for Diagnostic Testing for Adult Obstructive Sleep Apnea: An American Academy of Sleep Medicine Clinical Practice Guideline.Obstructive sleep apnea as an under-recognized cause of night sweats and the diagnostic workup approach. This is frequently under-recognized.

Lymphoma or other cancers: Less commonly, certain cancers — particularly lymphomas — present with what clinicians call 'B symptoms': fever, drenching night sweats, and unexplained weight loss together. This combination is the reason persistent, unexplained night sweats deserve a workup.

What tests will a clinician likely order?

A focused history is the most important step. Lab work often includes:

• Thyroid function tests (TSH, free T4) to rule out hyperthyroidism 5Ref 5Jonklaas J, Bianco AC, Bauer AJ, et al. (2014).Guidelines for the Treatment of Hypothyroidism: Prepared by the American Thyroid Association Task Force on Thyroid Hormone Replacement.Thyroid function tests as part of night sweats workup; hyperthyroidism as a cause of sweating and metabolic acceleration
• Complete blood count (CBC) for signs of infection, anemia, or blood disorders
• Comprehensive metabolic panel checking blood glucose, kidney, and liver function 6Ref 6American Diabetes Association Professional Practice Committee (2024).Standards of Care in Diabetes—2024.Nocturnal hypoglycemia in people on diabetes medications as a cause of night sweats; blood glucose testing in the workup
• HIV test — HIV is a well-established cause of night sweats 4Ref 4US Preventive Services Task Force; Owens DK, Davidson KW, Krist AH, et al. (2019).Screening for HIV Infection: US Preventive Services Task Force Recommendation Statement.HIV as a cause of night sweats and the recommendation to screen when etiology is unclear
• TB test (skin test or IGRA blood test) — recommended when any exposure risk exists
• Hormone panel (FSH, LH, estradiol or testosterone) to confirm or rule out hormonal causes [1, 2]
• Inflammatory markers (ESR, CRP) as general indicators of infection or inflammation

How to prepare for your appointment

Keep a brief log for one to two weeks: when sweats happen, how soaked you get, whether there is any fever, and any associated symptoms (weight loss, fatigue, cough, changes in mood or energy). Bring your full medication and supplement list. Note any recent infections, travel, or new stressors. The more specific you can be, the faster the workup.