Hypertension antihypertensive drugs

Hypertension infrequently results from another disease, such as a catecholamine-secreting tumor (pheochro-mocytoma) in most cases the cause carmot be determined essential (primary) hypertension. Antihypertensive drugs are indicated when blood pressure cannot be sufficiently controlled by means of weight reduction or a low-salt diet. In principle, lowering of either cardiac output or peripheral resistance may decrease blood pressure (cf p. 306,... 

Anti hypertensive Drugs. Table 1 Common side effects of antihypertensive drugs... 

If 50% of Europeans with essential hypertension are affected by this disease because of an elevated secretion of endogenous ouabain, then there might be a chance to block its interaction at the cardiac glycoside binding site of Na+/K+-ATPase and thus lower blood pressure. This therapeutic approach seems to be successfiil. Recent studies provide evidence that the cardenolide analogue Rostafuroxin (PST 2238 Fig. 4) at very low concentrations can overcome the ouabain-induced tise of hypertension in experimental animals [6]. This compound has recently entered the phase I of clinical trials and is certainly a prototype of a new class of antihypertensive drugs. 

Many antihypertensive drug lower the blood pressure by dilating or increasing the size of the arterial blood vessels (vasodilatation). Vasodilatation creates an increase in the lumen (the space or opening within an arteiy) of the arterial blood vessels, which in turn increases the amount of space available for the blood to circulate Because blood volume (the amount of blood) remains relatively constant, an increase in the space in which the blood circulates (ie, the blood vessels) lowers the pressure of the fluid (measured as blood pressure) in the blood vessels. Although the method by which anti-hypertensive drug dilate blood vessels varies, the result... 

Antihypertensives are used in the treatment of hypertension. Although many antihypertensive drugs are available, not all drag may work equally well in a given patient. In some instances, the primary care provider... 

Diaz oxide (Hyperstat IV) and nitroprusside (Nitropress) are examples of intravenous (IV) drugs that may be used to treat hypertensive emergencies. A hypertensive emergency is a case of extremely high blood pressure that does not respond to conventional antihypertensive drug therapy. 

Mr. Bates, who has been treated for hypertension, is admitted for treatment of a kidney done On admission, he had severe pain and his blood pressure was 16006 mm Hg. For the past 2 days, his blood pressure has been between 14002 and 14802 mm Hg. When taking his blood pressure before givijTg him an oral antihypertensive drug, you find that it now is 11802 mm Hg. A nalyze the situation and discuss what actions you would take... 

Strict compliance with antihypertensive drug regimen is important in patients witii known hypertension during epoetin tiierapy. 

Diuretics are used in a variety of medical disorders. The primary health care provider selects the type of diuretic diat will most likely be effective for treatment of a specific disorder. In some instances, hypertension may be treated with the administration of an antihypertensive drug and a diuretic. The diuretics used for this combination tiierapy include the loop diuretics and the thiazides and related diuretics. The specific uses of each type of diuretic drug are discussed in the following sections. 

TH E PATI ENT WITH HYPERTENSION. The nurse monitors the blood pressure, pulse, and respiratory rate of patients with hypertension receiving a diuretic, or a diuretic along with an antihypertensive drug, before the administration of the drug. More frequent monitoring may be necessary if the patient is critically ill or the blood pressure excessively high. 

The primary objective of a Phase I trial is to assess the safety of the drug in humans. Studies are normally conducted in healthy male volunteers, although specific categories of subject may be used in certain cases. For example, to avoid the risk of low blood pressure, subjects with mild hypertension would be more appropriate for the evaluation of antihypertensive drugs, while patients are likely to be used in the case of drugs that are expected to produce significant toxic effects (e.g. anti-cancer cytotoxic drugs). Remuneration may be offered for participation in the study. The number of subjects is normally between 10 and 100 people. 

Schunkert H, Hense H-W, Gimenez-Roqueplo AP. The angiotensinogen T235 variant and the use of antihypertensive drugs in a population-based cohort. Hypertension 1997 29 628-633. 

The six compelling indications identified by JNC 7 represent specific comorbid conditions for which clinical trial data support using specific antihypertensive drug classes to treat both hypertension and the compelling indication (see Fig. 10-2). 

Clearly, the ideal antihypertensive drug will be one which neutralizes a specific etiological factor responsible for the disease. Unfortunately, a specific etiology has not been found for the overwhelming number of hypertensive states in man. It is also becoming apparent that numerous factors regulate the blood pressure and that, therefore, numerous variables may be deranged in hypertension(6). Thus, an empirical approach is still necessary in the treatment of the hypertensive patients. 

Drugs that are used for treating hypertonic diseases as well as symptomatic hypertensions are called antihypertensive drugs. 

Depending on the severity of the hypertension, treatment with antihypertensive drugs proceeds strategically in a specific order. It is understood that this order should be flexible and open to alternative ways, but a few general principles must be adhered to. 

Guanethidine is used for severe hypertension when the use of the more generally accepted drngs turns out to be unsuccessful. It is a powerful, long-lasting antihypertensive drug however, it affects a patient s blood pressure only in the orthostatic position, and not when lying down. 

Angiotensin-converting enzyme inhibitors have turned out to be very effective antihypertensive drugs that have begun to overtake )3-adrenoblockers, especially in monotherapy of hypertension. 

Moreover, whether or not hypertension is caused by an elevated level of renin or other reasons, angiotensin-converting enzyme inhibitors lower both systolic and diastolic arterial pressure in hypertensive patients, and their effects are enhanced by diuretics. Angiotensin-converting drugs of this series (captopril, enalapril) are effective antihypertensive drugs used both independently and in combination with other drugs to treat all types of hypertension as well as to treat cardiac insufficiency. 

Minoxidil is a peripheral vasodilator that directly relaxes vascular smooth musculature, thus, lowering systolic and diastolic pressure. Its action is linked to the activation of calcium channels. Open calcium channels cause hyperpolarization of smooth muscle cells, which in turn, reduces the flow of calcium ions into the cell, which is necessary for supporting vascular tonicity. However, when taking minoxidil, tachycardia, elevated renin secretion, and water and sodium ion retention all appear simultaneously with hypotension. Because of potentially serious side effects, it is used only for severe hypertension that does not respond to treatment with other drugs, and absolutely in combination with two other antihypertensive drugs. A synonym of this drug is loniten. 

Anti hypertensive drug withdrawal syndrome - Antihypertensive drug withdrawal syndrome may occur after discontinuation of antihypertensives. 

Hypertension As the sole therapeutic agent or to enhance other antihypertensive drugs in more severe forms of hypertension. 

Edema Edema associated with CHF, hepatic cirrhosis, and renal disease, including the nephrotic syndrome. Particularly useful when greater diuretic potential is desired. Parenteral administration is indicated when a rapid onset of diuresis is desired (eg, acute pulmonary edema), when Gl absorption is impaired or when oral use is not practical for any reason. As soon as it is practical, replace with oral therapy. Hypertension (furosemide, oral torsemide, oral) A one or in combination with other antihypertensive drugs. 

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