Drugs
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Since their synthesis in the late 1800s paracetamol (acetaminophen) and phenacetin have followed divergent pathways with regard to their popularity as mild analgesic/antipyretic drugs. Initially, paracetamol was discarded in favour of phenacetin because the latter drug was supposedly less toxic. Today the opposite is true, and paracetamol, along with aspirin, has become one of the two most popular 'over-the-counter' non-narcotic analgesic agents. ⋯ Paracetamol damages the liver through the formation of a highly reactive metabolite which is normally inactivated by conjugation with glutathione. Overdoses of paracetamol exhaust glutathione stores, thus allowing the accumulation of this toxic metabolite which covalently binds with vital cell elements and can result in liver necrosis. Glutathione precursors (notably intravenous N-acetylcysteine) have proved remarkably successful in treating paracetamol overdose, as long as treatment is initiated within 10 hours.(ABSTRACT TRUNCATED AT 400 WORDS)
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An association between low serum potassium concentrations and ventricular arrhythmias has been observed by a number of investigators in patients with both acute myocardial infarction and symptomatic angina. The increased frequency of ventricular fibrillation in patients with low serum potassium concentrations has not been attributable to differences in the size or location of the infarct or concomitant digitalis administration. Although prior diuretic usage is frequently associated with a low serum potassium concentration, diuretic usage in the absence of significant changes in serum electrolytes is not associated with an increase in malignant ventricular arrhythmias. ⋯ Attempts to increase the serum potassium in acute cases do not appear to be successful in preventing ventricular arrhythmias in this setting. Primary prevention of electrolyte disturbances would seem to offer more effective protection against serious arrhythmias. Long term studies with beta-blockers support this premise.