Alpha-beta blockers

Diuretics or beta blockers-- 2. ACE inhibitors, calcium blockers, alpha-] blockers, alpha-beta blocker ... 

When BP control is needed during interventional procedures, one can use intravenous nitrates or combined alpha-beta blockers such as labetalol. When these agents fail,... 

The nurse is preparing to administer the alpha-beta blocker labetalol (Normodyne) intravenous push (IVP) to a client diagnosed with hypertensive crisis. Which intervention should the nurse implement ... 

Selertive serotonin reuptake inhibitors may decrease metabolism of alpha/beta blockers, benzodiazepines, carbamazepine, cimetidine, clozapine, fesoterodine, haloperidol, methadone, mexiletine, phenytoin, propafenone, respiradone, tamoxifen, galantamine, respiradone, thioridazine. 

Her medications included levothyroxine, an angiotensin-converting enzyme (ACE) inhibitor, an alpha beta-blocker, two diuretics, a nitrate, a lipid-lowering agent, and aspirin. 

Some of the side effects due to beta blockers such as the slowing of heart rate can be counteracted by administration of drugs which antagonize the alpha adrenergic receptors. The... 

ACE inhibitors - AT antagonists - Alpha blockers - Beta blockers Isolated syslolic hypertension (older patienls) - Diuretics preferred (generally Thiazides) - Long-acting dihydropyridine calcium channel blocker... 

Thyroid supplement Blood pressure medications Beta blockers Thiazide diuretics Alpha methyl DOPA Appetite suppressants Phentermine Sibutramine Other Alcohol Caffeine Cocaine Nicotine... 

Terazosin is an alpha-adrenoreceptor blocker that causes vasodilation and is used in the management of hypertension and benign prostatic hypertrophy. Beta-blockers and alpha-blockers can interact to induce hypotension since both act to reduce the blood pressure. Patients already on beta-blockers and who are started on alpha-blockers such as terazosin should be advised to take the terazosin dose at night to reduce the implications (falls) of first-dose hypotension. 

Deficiency of adrenal medullary catecholamines appears to give no ill effects, and replacement therapy is therefore not used, but adrenal medullary tumours, phaeochromocytomas, secrete excess catecholamines often causing hypertension with dramatic episodes of headache, palpitations, pallor, sweating and anxiety. This condition is normally treated surgically, but preoperative preparation is mandatory to avoid catastrophic effects of surges of catecholamine release. A combination of alpha- and beta-adrenergic receptor blockade is normally used, with drugs such as phenoxybenzamine or doxazosin as alpha-blockers, and propranolol as a non-selective beta-blocker. 

Geriatric Considerations - Summary Discontinuation of clonidine is likely to require a slow taper. If the patient is receiving a concomitant beta-blocker, the beta-blocker must be tapered and discontinued before discontinuing clonidine. Clonidine discontinuation in the presence of a beta-blocker can lead to severe hypertension and cardiovascular events due to unopposed alpha-receptor stimulation. CNS effects often preclude its use in older adults. A higher clonidine dose (0.4 mg/day) is generally needed to control peri- or postmenopausal vasomotor symptoms however, adverse effects often make it difficult to achieve effective doses. 

Beta Blockers with Additional Alpha Blocking Activity... 

The detailed pharmacology of alpha and beta blockers is already discussed in chapter Adrenergic blocking agents. Only adrenergic blockers used in hypertension are discussed here. 

Labetalol [Normodyne, Trandate). Labetalol is a nonselective beta blocker. This drug appears to have some alpha-1-selective blocking effects. Labetalol is used primarily in the management of hypertension and, while usually given orally, may be injected intravenously in emergency hypertensive situations. 

Propranolol [Inderal). Propranolol, the classic nonselective beta blocker, is approved for use in hypertension, angina pectoris, cardiac arrhythmias, and prevention of myocardial reinfarction. In addition, propranolol has been used in the prevention of vascular headache and as an adjunct to alpha blockers in treating pheochromocytoma. Propranolol is usually administered orally for the long-term management of the previously listed conditions, but it may be administered via intravenous injection for the immediate control of arrhythmias. 

Alpha-adrenergic antagonists are used primarily as antihypertensive drugs because of their ability to block vascular alpha-1 receptors. Beta-adrenergic antagonists (beta blockers) are administered primarily for their inhibitory effects on myocardial function and are used in the prevention and treatment of hypertension, angina pectoris, arrhythmias, and myocardial reinfarction. Many of the drugs introduced in this chapter are discussed further in chapters that deal with the specific clinical conditions (e.g., hypertension, asthma, and other disorders). 

Acute intoxication with amphetamine is associated with tremor, confusion, irritability, hallucinations and paranoid behaviour, hypertension, sweating and occasionally cardiac arrhythmias convulsions and death may occur. The cardiovascular effects of the stimulants may be treated by beta-blockers, or by the combined alpha- and beta-blocker labetalol calcium channel antagonists such as nifedipine may correct the arrhythmias, while intravenous diazepam is of value in attenuating seizures. 

Therapeutic Function Alpha-adrenergic blocker, Beta-adrenergic blocker. Antihypertensive... 

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