Expert review of clinical pharmacology
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Expert Rev Clin Pharmacol · May 2012
ReviewCriteria for acetylcysteine treatment and clinical outcomes after paracetamol poisoning.
Acetylcysteine is an effective antidote for paracetamol (acetaminophen) poisoning, but different treatment criteria exist internationally. In the UK, acetylcysteine is indicated by paracetamol concentrations higher than the Prescott nomogram or higher than 50% of the nomogram in patients with increased susceptibility to liver toxicity. In the USA, a single '150-line' nomogram has been used that removes the need for additional clinical risk assessment. ⋯ An existing database of 1191 patients admitted to hospital after paracetamol overdose identified that the 4-h equivalent paracetamol concentration was: ≥200 mg/l in 163 patients (15.6%; 95% CI: 13.3-18.2%), ≥150 mg/l in 264 (24.3%; 95% CI: 21.5-27.5%) and ≥100 mg/l in 426 patients (39.3%; 95% CI: 35.6-43.2%), and acute liver injury occurred in 3.7% (95% CI: 1.4-8.0%), 2.3% (95% CI: 0.8-5.0%) and 1.9% (95% CI: 0.8-3.7%), respectively. The different indications for acetylcysteine used by the UK and USA would result in similar numbers of patients treated, although the criteria would define patients with different characteristics and patterns of overdose. The relative merit of these different international approaches to acetylcysteine administration is considered in this article.
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Expert Rev Clin Pharmacol · May 2012
ReviewTicagrelor: a P2Y12 antagonist for use in acute coronary syndromes.
Agents that inhibit platelet function are used routinely in the treatment and prevention of acute coronary syndromes. The main antiplatelet treatments used combine aspirin with one of the thienopyridine P2Y(12) antagonists, either clopidogrel or prasugrel. By blocking the synthesis of thromboxane A(2) in platelets and by blocking the effects of ADP, respectively, these agents reduce platelet activity, platelet aggregation and thrombus formation. ⋯ In this article we provide an overview of ticagrelor. We discuss the differences in mode of action compared with other P2Y(12) antagonists, examine its pharmacodynamic, pharmacokinetic and safety profile, and summarize the various clinical trials that have provided information on its efficacy in combination with aspirin. Ticagrelor appears to overcome some of the difficulties that have been encountered with other antiplatelet treatments, clopidogrel in particular.