Doctors and health care professionals can lower a person's blood pressure immediately using intravenous medications during a hypertensive emergency, according to WebMD. Medications known as direct vasodilators dilate blood vessels to allow blood to flow under normal pressures. Two such medications are nitroprusside and diazoxide.
Drugs.com explains diazoxide is used in emergency situations when severe high blood pressure occurs in adults and children. This medication lowers diastolic pressure in children. The drug increases cardiac output when blood pressure lowers, thereby making the heart work less. Hyperglycemia may occur as a side effect, but that condition usually occurs in patients with diabetes. Repeated injections of diazoxide may result in congestive heart failure since the medication causes sodium retention.
Doctors use nitroprusside to maintain lower blood pressure during surgery, to treat life-threatening high blood pressure and to treat congestive heart failure. Doctors normally start with a lower dosage of the drug before administering higher doses to achieve the desired blood pressure reading. Common side effects of this strong medication include skin rash, redness and a warm feeling, notes RxList.
WebMD states the goal of lowering blood pressure immediately during a hypertensive emergency is to prevent further organ damage. Doctors may perform eye exams in a hypertensive emergency to monitor possible organ damage. Blood and urine samples are also taken. Symptoms of a hypertensive emergency include headache, blurred vision, seizure, increasing chest pain, increasing shortness of breath and fluid buildup in tissues.