Which of the following drugs is associated with the reaction of Cinchonism?

The correct answer is B. Quinidine. Quinidine causes cinchonism - a toxic syndrome characterized by tinnitus, headache, dizziness, nausea, and visual disturbances. This occurs because quinidine is derived from quinine (a cinchona bark alkaloid), and both share this toxicity profile when plasma levels become…

Principles of Therapeutics

Question

Options

AValproic acid
BQuinidine
CIsoniazid
DEthosuximide

How the community answered

(40 responses)

A
15% (6)
B
73% (29)
C
8% (3)
D
5% (2)

Explanation

Quinidine causes cinchonism - a toxic syndrome characterized by tinnitus, headache, dizziness, nausea, and visual disturbances. This occurs because quinidine is derived from quinine (a cinchona bark alkaloid), and both share this toxicity profile when plasma levels become elevated.

Why the distractors are wrong:

Valproic acid (A) - associated with hepatotoxicity, teratogenicity (neural tube defects), and thrombocytopenia, not cinchonism
Isoniazid (C) - causes peripheral neuropathy (B6 deficiency), hepatotoxicity, and drug-induced lupus
Ethosuximide (D) - associated with GI upset, Stevens-Johnson syndrome, and lupus-like reactions

Memory tip: Think "QUINidine = QUINine = CINCHona bark" - the "cin" in cinchonism directly links to the cinchona tree family. Tinnitus (ringing ears) is the classic board-tested symptom to associate with this drug.

Topics

#Quinidine#Cinchonism#Antiarrhythmics#Drug toxicity

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