Toxicity of chloroquine and hydroxychloroquine following therapeutic use or overdose.

Hydroxychloroquine is a generally well-tolerated medication. Short-term (days to weeks) toxicity includes gastrointestinal effects and rarely glucose abnormalities, dermatologic reactions, and neuropsychiatric events. Cardiotoxicity became of increased concern with its use in COVID-19 patients. Long-term (years) toxicities include retinopathy, neuromyotoxicity, and cardiotoxicity (conduction abnormalities, cardiomyopathy). Deaths from overdoses most often result from cardiovascular collapse.