Why does chronic myeloid leukaemia cause night sweats?

Night sweats are a common presentation of chronic myeloid leukaemia. They can range from feeling unusually hot to sweating enough to dampen sleepwear or bedding. The symptom can fluctuate, so a change from your own usual pattern is useful information for your care team.

Leukaemia cells and the body's immune response can release chemical messengers that affect the brain's temperature-regulating centre. Increased cell activity and inflammation may therefore lead to heat, sweating and disturbed sleep. Night sweats do not by themselves show whether the leukaemia has changed; infections, medicines, hormonal changes and a warm sleeping environment can also contribute.

Keeping track of when the sweating began, how often it occurs, whether it interrupts sleep, and any fever, chills, weight change or new tiredness can help put the symptom in context.

Tell the clinician managing your chronic myeloid leukaemia about new, worsening or drenching night sweats. They may review your symptoms, medicines and recent blood tests, and decide whether any further assessment is needed. Do not stop prescribed treatment or change its dose because of sweating without speaking with that team.

For comfort, keep water beside the bed, use breathable sleepwear and bedding, and have a dry change of clothes available. These measures can make sleep easier, but they do not replace checking a persistent change with a clinician.

Contact your oncology or haematology team promptly if night sweats are new, becoming more intense, repeatedly soaking clothes or bedding, or occurring with a measured fever, shaking chills, new cough, pain when passing urine, or feeling suddenly unwell. These features can need assessment for infection or another cause.

Seek urgent medical help for severe shortness of breath, chest pain, fainting, confusion, uncontrolled bleeding, or a rapidly worsening illness. If you are unsure how urgently to act, use the contact instructions your treatment team has given you.

Ask whether your recent symptoms and blood results suggest a need for additional tests, whether a medicine could be contributing, and which fever or infection symptoms should prompt an immediate call. You can also ask how to contact the team outside usual clinic hours.