Cinchonism
Cinchonism is quinine overdose causing tinnitus, vision loss, and cardiotoxicity.
Cinchonism is a pathological condition caused by an overdose of quinine or its natural source, cinchona bark. Quinine and its derivatives are used medically to treat malaria and lupus erythematosus, and in much smaller amounts as a bittering agent in tonic drinks. The condition is notable because it can occur from therapeutic doses of quinine, either from one or several large doses, and quinidine (a Class 1A anti-arrhythmic) can also cause cinchonism symptoms to develop with as little as a single dose.
Frequently Asked Questions
What is Cinchonism?
Cinchonism is a toxic reaction triggered by excessive intake of quinine or its natural source, cinchona bark. It can also be provoked by quinidine, a Class 1A anti-arrhythmic drug, even after a single dose.
What are the mild symptoms of Cinchonism?
Early signs include flushed and sweaty skin, ringing in the ears, blurred vision, headache, dizziness, and abdominal discomfort. Some patients also experience reversible high-frequency hearing loss, confusion, or skin rashes.
Can Cinchonism be fatal?
Yes, in severe cases it can lead to permanent deafness, blindness, anaphylactic shock, or dangerous cardiac rhythm disturbances. Death from cardiotoxicity is the most serious terminal outcome.
Is Cinchonism reversible?
Mild manifestations such as tinnitus, blurred vision, and high-frequency hearing loss are often reversible once the offending agent is withdrawn. However, severe presentations like permanent deafness, blindness, or cardiac damage may not fully resolve.
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