How do I know if I have malignant hypertension?

Very high BP. Malignant hypertension is high blood pressure that causes damage to organs in the body such as kidneys, heart, eyes, etc. In order to diagnose malignant hypertension, some organ damage must have occurred.
Malignant HTN? Your BP will almost always be over 120 diastolic, you may go blind from eye hemorrhages, you may die from kidney or heart failure. Your doctor can look into your eyes and see hemorrhage and exudates and a swollen disc. You your self may not know at all as it can be silent. This is the reason it is called the silent killer. Most are dead in 1 year with untreated malignant HTN.
It's rare. Malignant hypertension is an older term for a situation in which very high BP (usually chronic) causes brain swelling. The swelling can be detected by examination of the optic fundus (back of the eyeball) where protrusion of the optic nerve head is seen: this is termed papilledema. This condition may be associated with blurred vision.

Related Questions

Is it possible for a caffeine overdose to cause malignant hypertension? Can a caffeine overdose cause someone's blood pressure to increase from 140 to

No. I'm not entirely sure what a caffeine 'overdose' means here. Lots of coffee shouldn't do it. Real overdose with energy drinks or something like that are possibly another story. How about, just don't overdose on anything. It's bad. Read more...
Caffeine malign HTN. No caffeine will not cause malignant HTN. It will increase BP especially if you don't usually consume caffeine. If you are on dextroaphhetiamie it can cause severe HTN. Read more...