Toxicophysiology

Excessive b-receptor blockade predictably decreases inotropy, chronotropy, and metabolic effects that are expected from subunit stimulation, resulting in hallmark bradycardia and hypotension.

Other mechanisms may contribute to b-blocker toxicity. Several b-blocker drugs antagonize myocardial sodium channels (IabJe...169-1) in a manner similar to the effects of quinidine or cyclic antidepressants. Impedance of sodium entry slows phase zero of the action potential, resulting in prolonged QRS duration and myocardial depression. Thus, patients may present with wide-complex bradycardia.

Was this article helpful?

0 0
Peripheral Neuropathy Natural Treatment Options

Peripheral Neuropathy Natural Treatment Options

This guide will help millions of people understand this condition so that they can take control of their lives and make informed decisions. The ebook covers information on a vast number of different types of neuropathy. In addition, it will be a useful resource for their families, caregivers, and health care providers.

Get My Free Ebook


Post a comment