Severe, worsening headache
High fever
Confusion or altered mental state
Drowsiness or difficulty waking up
Seizures
Vision changes
Double vision
Swelling around the eyes
Pain with eye movement
Redness or bulging of one or both eyes
Stiff neck
Nausea or vomiting
Sensitivity to light
Weakness or numbness
Trouble speaking
Trouble walking or loss of balance
Facial swelling
Symptoms rapidly getting worse
New neurological symptoms
Seek emergency medical care immediately