Chills when sick: what to know

Shivering can happen as the body adjusts its internal temperature, including before or during a fever. Influenza may bring sudden chills, aches, cough and exhaustion. Pneumonia can cause chills with cough, chest discomfort or shortness of breath. A urinary tract infection or kidney infection may cause chills with burning urination, frequent urination or pain in the side or back.

Travel and exposure history matter. Malaria can cause episodes of fever and chills after time in a malaria area, while dengue fever may cause fever and marked aches after mosquito exposure. These illnesses are not diagnosed from chills alone. Sepsis is a serious response to infection and can involve rapid worsening, confusion or breathing problems.

Rest, drink enough fluid to keep urine reasonably pale, and dress in comfortable layers rather than overheating yourself. Check your temperature if possible and write down when the chills occur. Follow the label for any fever medicine and check with a pharmacist if you are pregnant, have liver or kidney disease, or take regular medicines. Keep distance from others if you have respiratory symptoms, improve ventilation and wash hands.

Contact a clinician promptly if chills keep returning, fever persists, a cough causes breathing difficulty, urination becomes painful, or you have severe pain, dehydration or a new rash. Seek emergency care for confusion, fainting, blue or grey lips, severe breathlessness, a seizure, cold clammy skin or rapid deterioration. After travel, report the countries and dates even if the trip was not recent.

Ask which symptoms point toward a respiratory, urinary or travel-related infection, whether an examination or testing is needed, and how to manage fever safely. Tell the clinician about medicines, pregnancy, chronic conditions, travel, mosquito exposure and contact with someone who was ill.