Which eye is affected: right or left? Both at the same time or one after the other? Which eye was reddened first?
Since when do the symptoms exist (hours, days or weeks), for the first time, repeatedly or always recurring, increasing intensity or frequency of the symptoms, possibly in connection …
… with other activities (reading, doing sports, cycling, swimming, welding, flexing, working with hammer and chisel, staying at the beach, in the garden, in the animal stable / on the farm, in the airplane, abroad)?
or other symptoms (watery or purulent discharge, sneezing attacks, skin rashes, joint complaints, dry mouth, head / face skin hypersensitivy or numbness, swelling in the throat / jaw area, blocked nose, burning sensation and pain when urinating)?
Does anyone else in your circle of relatives (children, grandchildren, partner) or acquaintances (work colleagues) have similar complaints?
Has the vision in the affected eye worsened recently?
Does blinking several times improve the vision?
Do you have a cold or fever?
Are you sensitive to light or glare?
Have you recently seen rainbow colors around light sources?
Are you taking any medications (pills, injections, or eye drops)?
Do you wear contact lenses?
Do you suffer from headaches, nausea or vomiting?
Is there an underlying disease?
Are there any known diseases in your own family (parents, grandparents, siblings)?