Having chills: understanding what they may mean

Chills are a sensation of cold or visible shivering. They can occur after being in a cool environment, with fear or stress, or as the body responds to an infection. Influenza, dengue fever and malaria may present with chills alongside other symptoms such as fever, headache or marked tiredness. Kidney infection and urinary tract infection can be associated with chills and urinary or back symptoms. Pneumonia may bring chills with cough or breathing symptoms. Sepsis is a dangerous response to infection and may cause chills with confusion, rapid breathing or severe illness. Chills do not identify one diagnosis by themselves.

Warm yourself gradually, rest and drink fluids if you can. Measure your temperature rather than relying on how hot or cold you feel. Write down when the chills start, how long they last, and any fever, cough, pain, urinary change, rash, travel or insect exposure. Avoid self-prescribing antibiotics; the right treatment depends on the cause. Arrange a clinical review when episodes repeat or do not have a clear explanation.

Seek emergency care for confusion, fainting, severe breathing difficulty, blue or mottled skin, extreme drowsiness, or a rapidly worsening condition. Get prompt medical advice for chills with a high temperature, new cough, painful urination, side pain, rash, vomiting, or recent travel where malaria or dengue occurs. A normal temperature does not rule out a serious illness, particularly in vulnerable people.

What accompanying symptoms help identify the cause? Should I test my temperature at particular times? Could my medicines or recent travel be relevant? What should I do if chills return while my temperature is normal?