Drugs and Medicines to Treat High Blood Pressure

What is Blood Pressure? All the tissues and organs of the body need nourishment in the form of oxygen, glucose, and minerals for their normal functioning. This nourishment is carried by the blood to various sites through the blood vessels by the pumping action of the heart. With each contraction of the heart, blood is pushed into the arteries. In healthy persons this pressure is normal, but in some it may be more than normal. This above normal pressure in the arteries is called high blood pressure or hypertension. In some cases it may be less than normal and is then termed low blood pressure or hypotension. Blood pressure has two components - Systolic (upper) and Diastolic (lower). It is written as 120/80 mm Hg which means 120 mm Hg systolic and 80 mm Hg diastolic. The abbreviation 'mm Hg' stands for millimeter of mercury. Correct Way to Measure BP: Routine office BP measurement is done in a sitting position. One has to sit quietly with back supported for 5 minutes and arm placed at the level of heart. Coffee tea or smoking are not allowed in the preceding hour. For establishing hypertension at least three readings, one week apart must be taken. At each sitting two readings should be taken to confirm diagnosis. Readings are taken in both arms and if there is a significant difference then the arm with higher reading is selected for subsequent measurements. In diabetics, BP is taken in supine or lying down position and repeated, 2 minutes later, in upright position. This is done to detect any fall in BP in upright position. This is very important in diabetics and elderly lest they may fall under the effect of medicines used to control hypertension. In a number of cases BP is higher in the physician's clinic than at home. This is due to a stress in the presence of doctor and is called as 'white-coat hypertension'. This phenomenon is more common in females. Self-check provide useful information on blood pressure response to treatment, may improve adherence to therapy and is useful in evaluating the extent of 'white-coat' hypertension. Home measurements can be done by 'dial type' variant of BP instrument, electronic self-inflating sets or by miniature versions which are placed on wrists. These instruments are reasonably accurate. However, they must be calibrated from time to time. This can be determined by measuring the blood pressure with an instrument called sphygmomanometer (BP measuring instrument). Normally, blood pressure varies from individual to individual, depending upon factors such as heredity, age, sex, nutrition, and body weight. A diastolic blood pressure of 90 mmHg or above is classified as hypertension and requires medical consultation. The treatment of BP is generally determined by the rise of systolic and diastolic BP. However, one should not get apprehensive if the BP goes above the normal limit once in a while. Types and Causes of Hypertension: Hypertension has been divided into two categories: essential or primary hypertension, and secondary hypertension. The exact cause of primary or essential hypertension is not known but there is generally a narrowing of the blood vessels. In secondary hypertension, there is involvement of other organs or systems such as the kidney, adrenal glands, and disorders like toxaemia of pregnancy. In secondary hypertension, the cause can be treated and blood pressure brought to normal. Primary hypertension lasts a lifetime and needs continuous treatment. Almost 90% cases of hypertension are of primary variety. Syndrome-X is given to a constellation of obesity, high BP, insulin resistance and raised blood lipids. It is commonly seen in our country.When Does Blood Pressure Become High? BP depends upon three important factors: force of contraction, the rate of beating of the heart, and the resistance to blood flow caused by the inner diameter of the blood vessels. Besides these, the volume of blood may also affect the BP. It is a common experience that emotional trauma or excitement, physical exercise or exertion increase the heart rate, which is experienced in the form of palpitation (bouncing or beating of the heart against the chest wall), resulting in a rise in BP. This is generally short-lived and does not require any treatment. The dangerous form of high BP is one which persists on repeated examinations. What Happens When the Blood Pressure Is High? The symptoms of high blood pressure may be related to elevated pressure itself, a disease of the blood vessel, or some other underlying diseases responsible for elevation of blood pressure. The most common symptom of elevated blood pressure is headache, specially in the back portion of the head. This is usually more severe when the person wakes up in the morning. Other symptoms are dizziness, giddiness, palpitation, and easy fatigability. In more severe cases the symptoms are bleeding through the nose or blood in the urine, blurring of vision due to changes in the arteries of the retina (screen for vision in the eye), incidence of dizziness or fainting due to transient decrease in blood flow to the brain, pain in the chest, and breathlessness. When blood supply of brain is drastically reduced, paralysis or 'stroke' may occur.It is a well-established fact that hypertension may be both the cause and effect of heart or kidney disorders, and may decrease the life expectancy of a person. Statistics show that hypertension, if untreated, shortens the life span of a person. There is 2-4 fold increase in ischaemic heart disease. High blood pressure is also the second most common cause of kidney failure. It is, therefore, important to detect the cause early and start the treatment. The treatment consists of general measures and drugs therapy. Any BP above 140/90 mm Hg should be treated. New evidence shows that BP should be kept below 130/80 mm Hg in pregnancy. diabetes and kidney disease.