What should you know about shivering and sweating but no fever?

Chills are muscle contractions that create warmth, while sweating cools the skin; both can occur during a rapid change in temperature or strong emotion. A normal reading does not exclude an illness, especially if symptoms are early, intermittent, or a fever medicine was taken. Influenza, pneumonia, kidney infection, urinary tract infection, dengue fever, and malaria can present with chills or sweating among other symptoms. Sepsis is a serious response to infection and may cause feeling very unwell, fast breathing, confusion, or clammy skin. The absence of fever should not override those warning signs.

Measure your temperature with the same reliable thermometer when symptoms occur and record the time, triggers, medicines, travel, insect exposure, and accompanying symptoms. Rest, drink fluids if you can, and change damp clothing. Do not pile on heavy blankets if you are sweating. Arrange a clinical review if episodes recur, last beyond a brief spell, or occur with cough, painful urination, back pain, vomiting, rash, or unusual fatigue.

Seek emergency help for confusion, fainting, severe shortness of breath, blue or grey lips, severe weakness, or rapidly worsening illness. Get same-day advice for shaking chills after travel to a malaria area, a new rash with marked illness, or urinary or chest symptoms. Do not wait for a fever reading if you feel seriously unwell.

Could an infection explain these episodes despite a normal temperature? Do I need urine, blood, or respiratory tests? Could a medicine, hormone change, or blood-sugar problem contribute? What symptoms require emergency care?