Fever and headache only: what to know

Some illnesses begin with fever and headache before cough, congestion, stomach upset or body aches appear. A common cold or COVID-19 may declare itself over time. Dehydration, hot surroundings, prolonged activity and poor sleep can also contribute to head pain, while allergic rhinitis more often causes nasal symptoms without a true fever. Dengue fever deserves consideration after relevant travel or mosquito exposure, especially if strong muscle and joint aches or a rash develops. Isolated symptoms do not establish the cause.

Check your temperature with the same method each time, note the timing of headache, and drink regularly. Rest away from direct heat and reduce intense exercise. Keep a record of new symptoms such as cough, sore throat, vomiting, rash, neck stiffness or light sensitivity. Follow label instructions for any fever or pain medicine, and ask a pharmacist before taking it if you have long-term conditions or use other medicines.

Get emergency help for a sudden or extreme headache, confusion, fainting, seizure, stiff neck, severe light sensitivity, breathing difficulty, new weakness, or a rash with serious illness. Arrange medical advice promptly if the fever or headache is worsening, keeps returning, you cannot drink normally, or you are passing very little urine. Seek earlier guidance for a baby, an older adult, pregnancy, reduced immunity or a significant chronic illness.

Ask what temperature pattern matters, whether an examination or test is appropriate, and how long home monitoring is reasonable. Tell the clinician about travel, heat exposure, mosquito bites, recent contacts, medicines and any change in alertness or hydration.