RESUMO
The current recommendations for monitoring digoxin, a narrow therapeutic index drug, are limited to confirming medication use or investigating suspicion of toxicity and fail our oath to do no harm. Numerous meta-analyses evaluating digoxin use consistently recommend frequent monitoring to maintain the level of 0.5 to ≤1.0â ng/ml because higher levels lead to increased morbidity and mortality without benefit. Data from the United States National Poison Control Center (2012-2020) show annual deaths due to digoxin of 18-36 compared to lithium's 1-7, and warfarin's 0-2 respectively. The latter drugs also have narrow therapeutic indexes like digoxin yet are more carefully monitored. Recognition of digoxin toxicity is impaired as levels are not being routinely checked after medications are added to a patient's regimen. In addition, providers may be using ranges to guide treatment that are no longer appropriate. It is imperative that monitoring guidelines and laboratory therapeutic levels are revised to reduce morbidity and mortality due to digoxin. In this review, we provide a comprehensive literature review of digoxin monitoring guidelines, digoxin toxicity, and evidence to support revising the ranges for serum digoxin monitoring.
RESUMO
Tyrosine kinase inhibitors (TKIs) are used for the targeted treatment of solid cancers. TKIs produce a variable incidence of liver adverse events (5-25%) which can progress to severe liver injury in a minority of patients if treatment is maintained despite ongoing injury. This risk requires careful patient management to maintain treatment benefit without harm. This review highlights the various mechanisms of idiosyncratic hepatotoxicity, the formation of reactive metabolites and how this leads to toxicity. These critical events depend of the drug-specific characteristics of each TKI and the patient risk factors, especially genetic characterization. With improved understanding of the mechanisms leading to hepatotoxicity, several strategies have been adopted to prevent or treat this side effect. Recommendations on liver function liver test monitoring have been proposed according to each TKI.