Hypotensive drug

Postural hypotension contributes to the risk of syncope and falls especially in the elderly (Verhaeverbeke and Mets 1997). In case of postural hypotension, drug treatment should always be reviewed. Due to a decrease in homeostatic mechanisms elderly more often have postural hypotension from drugs that lower blood pressure than younger patients (Turnheim 1998). It is not only cardiovascular drugs that may... 

The effect of a substance depends on the amount administered, i.e., the dose. If the dose chosen is below the critical threshold (subliminal dosing), an effect will be absent. Depending on the nature of the effect to be measured, ascending doses may cause the effect to increase in intensity. Thus, the effect of an antipyretic or hypotensive drug can be quantified in a graded fashion, in that the extent of fall in body temperature or blood pressure is being measured. A dose-effect relationship is then encountered, as discussed on p. 54. 

Antihypertensive drugs can be divided into eight classes based on the mechanism of action diuretics, )3-adrenoblockers, centrally acting sympatholytics, peripherally acting sympatholytics, calcium channel blockers, myotropic hypotensive drugs, angiotensin-con-verting enzyme inhibitors, and calcium channel activators. 

Drugs Alcohol, narcotics, hypotensive drugs, chemotherapeutic agents, steroids, diethylstilbestrol... 

The wide-spread and diverse functions of NO in biology can be mediated through metallonitrosyl complexes. This opens the way for the coordination chemist to design new agents as 1) cytotoxic drugs that are activated by reduction in vivo to release NO 2) more versatile hypotensive drugs 3) facilitators of penile erection that might be applied topically, possibly in... 

All hypotensive drugs lower systemic BP but, due to the specific characteristics of the glomerular capillary system, different agents may affect glomerular hemodynamics in different ways. This could be of major importance. During antihyper-tensive therapy, systemic BP may be reduced but glomerular pressure may be elevated. This may explain why the incidence of some cardiovascular complications such as stroke, has decreased, whereas the incidence of hypertensive nephropathy has remained high. 

Guanethidine, rarely used as a hypotensive drug, also causes some catecholamine depletion, but unlike reserpine it does not cross the blood-brain barrier and thus has no central sedative effects. It acts selectively because it is taken up into the neuron by the same amine pump that transports the neurotransmitter. 

Because adrenergic agents such as P-blockers find such extensive use as hypotensive drugs, the etiology and drug combination treatment of hypertension are of considerable interest. A discussion in any detail of this complex and confusing field goes beyond the scope of this book, however. Other aspects of hypertension will be discussed in connection with the renin and vasopressin systems and calcium channel blockers. 

Monoamine oxidase inhibitors (MAOIs) are useful as thymoleptic (antidepressant) drugs, especially since the action of some of these agents is very rapid, as compared to the lag period of days or even weeks shown by tricyclic antidepressants. All MAOIs act by increasing the available concentration of the neurotransmitters NE and 5-HT which, because they are not metabolized, accumulate in the synaptic gap and exert an increased postsynaptic effect. The drugs show hypotensive activity as a side effect, and some MAOIs are used as hypotensive drugs. 

Verapamil, diltiazem Nonselective block of L-type calcium channels in vessels and heart Reduced vascular resistance, cardiac rate, and cardiac force results in decreased oxygen demand Prophylaxis of angina, hypertension, others Oral, IV, duration 4-8 h Toxicity Atrioventricular block, acute heart failure constipation, edema Interactions Additive with other cardiac depressants and hypotensive drugs... 

Propranolol 13- Adrenoceptor blockade Direct membrane effects (sodium channel block) and prolongation of action potential duration slows SA node automaticity and AV nodal conduction velocity Atrial arrhythmias and prevention of recurrent infarction and sudden death Oral, parenteral duration 4-6 h Toxicity Asthma, AV blockade, acute heart failure Interactions With other cardiac depressants and hypotensive drugs... 

Stripping voltammetry has recently received a great deal of interest due to its high sensitivity and rapid direct assay (see Sec. III.F). Examples using stripping voltammetry for the trace-level determination have included assays for penicillins [121], diltiazem (calcium channel blocker) [122], mitomycin C (quinone-containing antitumor antibiotic) [123], captopril (hypotensive drug)... 

One old-fashioned augmentation strategy that has fallen out of favor in recent years is to combine with great caution a TCA and an MAO inhibitor (the cautious combo in Fig. 7—30). Given its potential dangers (e.g., sudden hypertensive episodes, orthostatic hypotension, drug and dietary interactions, obesity), as well as the wide variety of other antidepressant combinations available today, this combination is rarely necessary or justified. 

M. E. Jung and T. Shaw, Total synthesis of (R)-glycerol acetonide and the antiepileptic and hypotensive drug (-)-y-amino-/l-hydroxybutyric acid (GABOB) use of vitamin C as a chiral starting material, J. Am. Chem. Soc., 102 (1980) 6304-6313. 

Kobinger W (1978) Central a adrenergic systems as targets of action for hypotensive drugs. Rev Physiol Biochem Pharmacol 8 40-100... 

Box 10-1 Ocular Hypotensive Drugs Used to Treat Glaucoma... 

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