12 - Antihypertensive and anti-anginal drugs

Abstract

This review discusses the main clinical features and management of the antihypertensive–anti-anginal agents in common clinical overdose. Acute poisoning with antihypertensive and anti-anginal drugs is uncommon. Hypotension and dysrhythmias are the main complications so most cases of deliberate overdose require monitoring in an intensive care facility. Emesis or lavage may be helpful if a large overdose has been taken. Sudden loss of consciousness has been described with clonidine and vomiting is best avoided in this type of poisoning. Activated charcoal when administered at adequate dose (10 times the weight of the suspected overdose) is an effective adsorbent for the drugs under discussion. In most cases, hypotension can be treated using simple measures such as intravenous saline and elevating the legs. Symptomatic bradycardia often responds to atropine but when combined with hypotension and low cardiac output, an inotropic agent such as dopamine, dobutamine, or noradrenaline may be required. Arrhythmias due to hypokalemia require electrolyte replacement while glucose/insulin, cation exchange resins, and hemodialysis may be required for hyperkalemia. Electrical pacing is indicated for severe sustained arrhythmias.