Also known as pseudotumor cerebri/benign<unk><unk>  (BIH)
Cause is<unk> , but believed be due to impaired CSF absorption at arachnoid villi
Associated with obesity, weight gain, pregnancy, cyclosporine, OCPs, vitamin A >100,000 U/day, tetracycline, amiodarone, sulfa antibiotics, lithium, thyroid disorders, and historically nalidixic acid (rarely used). Systemic steroid intake and withdrawal may also be causative.
Idiopathic intracranial hypertension
Migraine headache
Subarachnoid hemorrhage
Tension headache
Post-lumbar puncture headache
Cluster headache
Subdural hemorrhage
Meningitis/encephalitis