Cinchonism

Cinchonism is a collection of symptoms stemming from the ingestion of quinoline derivatives and its subsequent neural, retinal, and auditory toxicity. Ingestion of quinoline derivatives can produce a multitude of detrimental effects. Cinchonism is a subset of these effects originally believed to be primarily neurally mediated. This definition does not include the pro-arrhythmic properties of these drugs. It is commonly described as tinnitus, reversible hearing loss, flushing, confusion, diarrhea, and visual disturbances, including permanent blindness in some cases. In addition, some literature includes ataxia, tremor, and dystonic reactions as a part of cinchonism. Quinoline derivatives are used for a multitude of reasons, including as a class IA antiarrhythmic (quinidine), an anti-malarial agent, and for certain viral infections, including SARS-CoV-2 for a period of time. This article further elucidates the full spectrum of cinchonism.