Febrile seizure without fever: what to know

Febrile seizures happen with a raised temperature, usually during an illness. If there is no fever before, during, or soon after the event, clinicians consider other explanations, such as epilepsy, low blood sugar, an infection affecting the brain, a recent head injury, medicine or substance exposure, or a faint that resembles a seizure. A temperature can be missed if it was checked late, after cooling medicine, or with an unreliable reading, so tell the clinician exactly when and how it was measured.

Protect the person from nearby hazards, cushion the head, loosen tight clothing, and turn them onto their side when possible. Time the movements. Do not restrain them, put anything in the mouth, or give food, drink, or tablets until they are fully alert. Note breathing, colour, movements, responsiveness, possible injury, and what happened beforehand. A video can help a clinician if it is safe to record it.

Call emergency services if the seizure lasts longer than five minutes, repeats without recovery, affects breathing, causes a serious injury, happens in water, or the person remains unusually drowsy or confused. Seek urgent assessment for a first seizure without fever, especially with severe headache, stiff neck, rash, weakness, diabetes, pregnancy, or possible poisoning. Possible causes may include [Hypoglycaemia](/conditions/hypoglycaemia/) or [Meningitis](/conditions/meningitis/).

Ask whether tests are needed to check glucose, infection, medicines, or an electrical disturbance in the brain; whether an EEG or scan is appropriate; and what seizure-safety plan to follow at home. Mention any alcohol withdrawal or heavy use because [Alcohol Use Disorder](/conditions/alcohol-use-disorder/) can be relevant to seizure assessment.