Sympathomimetic drug agents

One of the most important uses of sympathomimetic drugs is in the therapy of bronchial asthma. This use is discussed in Chapter 20. Nonselective drugs (epinephrine), -selective agents (isoproterenol), and B2-selective agents (albuterol, metaproterenol, terbutaline) all are available for this indication. Sympathomimetics other than the 32-selective drugs are now rarely used because they are likely to have more adverse effects than the selective drugs. 

HKR has been used in a short synthesis of (R)-(-)-phenylephrine hydrochloride (9), an adrenergic agent and P-receptor sympathomimetic drug (Scheme 9.14).117... 

Catecholamines are sympathomimetic drugs. Dopamine and norepinephrine are used as vasopressors (antihypotensives). Epinephrine is used as a vasoconstrictor, cardiac stimulant, or bronchodilator to counter allergic reaction, anesthesia, and cardiac arrest. It is also an antiglaucoma agent. 

Interactions of MAOIs with other sympathomimetic drugs are well known. The increased neuronal stores of NE represent a booby-trap hazard that can easily be triggered by indirectly acting adrenergic agents such as the amphetamines found in many antiobesity preparations. Drugs such as ephedrine, phenylpropanolamine, and phenylephrine are potentially more dangerous because of their ready availability to the public in over-the-counter medications such as cold medicines and nose drops. 

Describe the potential toxicities of sympathomimetic drugs used as pressor agents. 

In the decompensated patient who presents with heart failure and normal systemic vascular resistance, afterload reduction may be contraindicated, and treatment with a parenteral agent such as dobutamine may be preferable. The risk attendant to treatment with sympathomimetic drugs is related to the increase in myocardial Oj consumption that may occur this is of particular concern in patients with left heart failure that occurs as a direct consequence of myocardial ischemia. This clinical quandary has become less common in the era of aggressive myocardial revascularization when it is encountered, coadministration of dobutamine with parenteral nitroglycerin should be considered. 

Sympathomimetic drug. Less potent than (5)-isomer. Resolving agent. 

Omission of the side chain hydroxyl group from molecules based on epinephrine or ephedrine does not abolish the sympathomimetic activity of the resulting compounds. Many of these agents exert a considerable stimulant action on the central nervous system. As such, drugs in this class have been widely used—and... 

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