Idiopathic intracranial hypertension (IIH) is when pressure in your head rises, causing vision problems and headaches. This high pressure comes from cerebrospinal fluid (CSF) that does not flow out of the brain as it should. The pressure affects the eye’s optic disc and nerve, eventually causing vision loss.

IIH is more common in young, overweight women, and hormones are the suspected cause. Sometimes children and adults who are not overweight have IIH. Antibiotics, steroids or high doses of vitamin A can also cause IIH.

Treatment may not be needed if symptoms are not severe. But if they are, medicine or surgery may be recommended to help lower pressure in the head.