Sudden, severe headache
Headache after a head injury
Nausea or vomiting
Confusion or trouble thinking clearly
Drowsiness or difficulty staying awake
Weakness or numbness on one side of the body
Trouble speaking or understanding speech
Vision changes
Loss of balance or coordination
Seizures
Fainting or loss of consciousness
Unequal pupil size
Slurred speech
Sudden severe neck pain
Blood or clear fluid from the nose or ears after injury
Worsening symptoms over time
Call emergency services immediately if these symptoms occur