Are Night Sweats a Sign of Lymphoma?

Usually not. Night sweats are common. Most of the time they come from menopause, an infection, anxiety, alcohol, or a warm bedroom. Lymphoma, a cancer of the lymph system, is an uncommon cause. But drenching night sweats that keep happening, especially with other symptoms, are worth a doctor's look.

Doctors call this pattern "drenching." You wake up soaked, and you may need to change your shirt or even your sheets. It happens repeatedly, not just on one hot night. In lymphoma, doctors group these sweats with two other symptoms: fever with no clear cause, and weight loss you did not try to lose. Together, these three are called "B symptoms." Having all three, or even two, makes a doctor think harder about a blood cancer.

Night sweats from lymphoma rarely show up alone. The National Cancer Institute lists painless, swollen lymph nodes in the neck, underarm, or groin as a key symptom of Hodgkin lymphoma. Lymph nodes are small, bean-shaped glands that are part of your immune system. A lymphoma-related node is usually painless, which is a useful clue, since a node swollen from a cold or skin infection is often tender. Itchy skin, especially after a warm bath or drinking alcohol, is another symptom the NCI lists alongside B symptoms.

Menopause is one of the most common causes of night sweats, from the hormone shifts that come with it. Infections, from a simple cold to more serious illnesses, can cause sweating at night while your body fights them off. Anxiety, alcohol before bed, spicy food, and a warm or heavily covered bed can all do it too. Some medicines, including certain antidepressants and drugs that lower fever, list night sweats as a side effect. Most people who bring up night sweats with a doctor turn out to have one of these ordinary causes.

Your doctor asks how often the sweats happen, how long this has gone on, and whether you have noticed fever, weight loss, or a lump. A physical exam checks your lymph nodes, spleen, and general health. Blood tests, including a complete blood count, often come next, since they can point toward infection or a blood cell problem. If a lymph node feels concerning, or blood tests raise questions, the next step is usually a biopsy: removing all or part of the node to look at under a microscope. Ask when the pathology result should be back and who will call you. Imaging such as a CT or PET scan may follow if lymphoma is confirmed, to see how far it has spread.

If your exam and blood work come back normal but the night sweats keep happening for more than a few weeks, say so at a follow-up visit. Persistent, unexplained symptoms are worth a second look, even after an initial normal workup.

• Call your care team the same day if the sweats arrive with a temperature of 100.4°F (38°C) or higher and you feel genuinely unwell, or if a swollen node has grown noticeably in a matter of days.
• Call your care team within a day or two if you are soaking your nightclothes or sheets most nights and it has gone on beyond two to three weeks, or the sweats now come with weight you did not try to lose or a painless lump in the neck, underarm or groin.

• I have drenching night sweats [how often] — what could be causing them?
• Could this be menopause, an infection, or a medicine side effect?
• Should I be checked for swollen lymph nodes?
• What other symptoms should I watch for?

• National Cancer Institute — Adult Hodgkin Lymphoma Treatment (PDQ)
• National Cancer Institute — Adult Non-Hodgkin Lymphoma Treatment (PDQ)