The headache can be made worse by any activity that further increases the intracranial pressure, such as coughing and sneezing.

Those who do experience symptoms typically report "transient visual obscurations", episodes of difficulty seeing that occur in both eyes but not necessarily at the same time.

Long-term untreated papilledema leads to visual loss, initially in the periphery but progressively towards the center of vision.

Longstanding papilledema leads to optic atrophy, in which the disc looks pale and visual loss tends to be advanced.

Intracranial pressure may be increased due to medications such as high-dose vitamin A derivatives (e.g., isotretinoin for acne),[10] long-term tetracycline antibiotics (for a variety of skin conditions).

[12] A systematic review published in 2020 suggests the use of the term "drug-induced intracranial hypertension (DIIH)" after having applied a 'strict drug-causality algorithm' in determining IIH cases likely caused by the drugs they evaluated.

[9] On July 1, 2022, the FDA issued an update that gonadotropin-releasing hormone agonists, drugs that are approved for treating precocious puberty, may be a risk factor for developing pseudotumor cerebri.

The Monro–Kellie rule states that the intracranial pressure is determined by the amount of brain tissue, cerebrospinal fluid (CSF) and blood inside the bony cranial vault.

Little evidence has accumulated to support the suggestion that increased blood flow plays a role, but recently Bateman et al. in phase contrast MRA studies have quantified cerebral blood flow (CBF) in vivo and suggests that CBF is abnormally elevated in many people with IIH.

In IIH these scans typically appear to be normal, although small or slit-like ventricles, dilatation and buckling[18] of the optic nerve sheaths and "empty sella sign" (flattening of the pituitary gland due to increased pressure) and enlargement of Meckel's caves may be seen.

[5][7][8] A contrast-enhanced MRV (ATECO) scan has a high detection rate for abnormal transverse sinus stenoses.

Lumbar puncture is performed to measure the opening pressure, as well as to obtain cerebrospinal fluid (CSF) to exclude alternative diagnoses.

If the suspicion of problems remains high, it may be necessary to perform more long-term monitoring of the ICP by a pressure catheter.

Bariatric surgery can be an option for those patients that don't achieve weight loss with lifestyle changes and diet.

Repeated lumbar punctures are regarded as unpleasant by people, and they present a danger of introducing spinal infections if done too often.

[5][7] Repeated lumbar punctures are sometimes needed to control the ICP urgently if the person's vision deteriorates rapidly.

[9] The best-studied medical treatment for intracranial hypertension is acetazolamide (Diamox), which acts by inhibiting the enzyme carbonic anhydrase, and it reduces CSF production by six to 57 percent.

It can cause the symptoms of hypokalemia (low blood potassium levels), which include muscle weakness and tingling in the fingers.

Also, in human beings it has been shown to cause metabolic acidosis as well as disruptions in the blood electrolyte levels of newborn babies.

[16] A self-expanding metal stent is permanently deployed within the dominant transverse sinus across the stenosis under general anaesthesia.

Two main surgical procedures are used for the treatment of IIH: optic nerve sheath decompression and fenestration and cerebral shunting.

[9] Shunt surgery, usually performed by neurosurgeons, involves the creation of a conduit by which CSF can be drained into another body cavity.

The initial procedure is usually a lumboperitoneal (LP) shunt, which connects the subarachnoid space in the lumbar spine with the peritoneal cavity.

These shunts are inserted in one of the lateral ventricles of the brain, usually by stereotactic surgery, and then connected either to the right atrium of the heart or the peritoneal cavity.

In various case series, the long-term risk of one's vision being significantly affected by IIH is reported to lie anywhere between 10 and 25%.

Overweight and obesity strongly predispose a person to IIH: women who are more than ten percent over their ideal body weight are thirteen times more likely to develop IIH, and this figure goes up to nineteen times in women who are more than twenty percent over their ideal body weight.

[7] From national hospital admission databases it appears that the need for neurosurgical intervention for IIH has increased markedly over the period between 1988 and 2002.

[28] For instance, the otitic hydrocephalus reported by London neurologist Sir Charles Symonds may have resulted from venous sinus thrombosis caused by middle ear infection.

[19][28] The terms "benign" and "pseudotumor" derive from the fact that increased intracranial pressure may be associated with brain tumors.

Negative reports on shunting in the 1980s led to a brief period (1988–1993) during which optic nerve fenestration (which had initially been described in an unrelated condition in 1871) was more popular.