Chills after a fever breaks

A fever changes the brain's temperature setting. When that setting moves back toward normal, you may feel cold and shiver even while your measured temperature is falling. Sweating, tiredness, muscle aches, and mild weakness can occur at the same time. The episode should gradually settle as you warm up and replace fluids.

Chills can also occur when an infection is still active or when a new temperature rise is beginning. Influenza, pneumonia, a kidney infection, malaria, and dengue fever are among conditions that can include fever and chills. Chills themselves do not identify the cause.

Rest, sip water or an oral rehydration drink, and use light layers or a blanket until the shivering eases. Check your temperature with the same thermometer if you feel hot or cold again. Follow the label or a clinician's instructions for any fever medicine, and avoid taking more than one product containing the same ingredient. Note when the chills began and whether fever, cough, painful urination, rash, or abdominal pain returns.

Get urgent help for confusion, fainting, trouble breathing, blue or grey lips, a seizure, severe weakness, a stiff neck, or skin that is unusually cold and mottled. Seek prompt medical advice if shaking is intense, fever returns repeatedly, you cannot keep fluids down, you are passing very little urine, or you have a weakened immune system. A clinician may need to examine you and test for infection.

Ask what could explain the timing of the chills, which symptoms should trigger urgent review, how often to check your temperature, and which medicines are suitable for you. Mention recent travel, insect bites, new medicines, pregnancy, and any urinary, breathing, or abdominal symptoms.