If left untreated, blood pressure tend to rise slowly and steadily over a number of years. sometimes, however, a very high blood pressure develops quite suddenly, with diastolic pressure shooting over 130 mm Hg. for hours or a days at a time. Systolic pressure can reach 250 mm Hg. or more. such a sharp increase could signal the onset of malignant hypertension.
though rare, this is very serious and must be treated by a physician as soon as possible. malignant hypertension can damage blood vessels in the kidney,eyes, or brain. left untreated, it can be fatal within six months.
thankfully, malignant hypertension can be brought under control very quickly with intravenous injections of the proper drugs- but rapid diagnosis and treatment are essential.