P-adrenergic drugs

The nurse should withhold the administration of a p -adrenergic drug, such as propranolol (Inderal), and contact the primary health care provider if the patient has a heart rate of less than 60 bpm or if there isany irregularity in the patient s heart rate or rhythm. 

Elenkov, IJ. et al., Modulation of lipopolysaccharide-induced tumor necrosis factor-a production by selective a- and P-adrenergic drugs in mice, J. Neuroimmunol., 61, 123, 1995. 

Among the indole derivatives which have found use as drugs are indo-methacin, one of the first non-steroidal anti-inflammatory agentsfll], sumatriptan, which is used in the treatment of migraine headaches[12] and pindolol[13], one of the p-adrenergic blockers. 

P-Adrenergic receptor 2 Amino acid variants moderately associated with receptor function and agonist induced down regulation. Some variants may predispose to some types of asthma and modulate action of p-2-adrenergic drugs. 

Vasodilators. Hydralazine causes direct relaxation of arteriolar smooth muscle. An important consequence of this vasodilation, however, is reflex tachycardia (T CO). It may also cause sodium retention (T plasma volume). The resulting increase in CO tends to offset effects of the vasodilator. Therefore, these drugs are most effective when administered along with sympathetic agents such as P-adrenergic receptor antagonists, which prevent unwanted compensatory responses by the heart. 

Esmolol hydrochloride is a competitive p-adrenergic receptor antagonist it is selective for pT adrenoceptors. In contrast to pindolol, esmolol has little intrinsic sympathomimetic activity, and it differs from propranolol in that it lacks membrane stabilizing activity Of all of the p-adrenergic blocking drugs, this compound has the shortest duration of action because it is an ester, it is hydrolyzed rapidly by plasma esterases and must be used by the intravenous route Esmolol is approved only for the treatment of supraventricular arrhythmias... 

Clinical reports on minoxidil indicate that the drug is effective, particularly in cases which are refractory to other drugs (21. 22). It has the typical side-effects of a vasodilator and co-administration of a diuretic and a p-adrenergic blocker is recommended in many of the reported studies (21-28). 

Derivatives of phenylethanolamine substituted by a phenolic hydroxyl on the para position have been known for some time to exhibit p-adrenergic agonist activity. As a consequence of this property, the compounds have proven useful as bronchodilators for the treatment of asthma (see Chapter 3). Since such sympathomimetic drugs tend to have undesired activity on the cardiovascular system in addition to the desired activity on the bronchii, considerable work has been devoted to the preparation of compounds that would show selectivity for the adrenergic receptors (P2) that predominate in the lung. Attachment of the side chain to a heterocyclic aromatic phenol has been one avenue that has shown promise for achieving this selectivity. 

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