Chloroquine toxicity causes all except ?
**Core Concept**
Chloroquine toxicity is a well-documented side effect of long-term or high-dose use of this antimalarial drug. It primarily affects the visual system and the cardiovascular system, leading to a range of clinical manifestations.
**Why the Correct Answer is Right**
Chloroquine toxicity is characterized by the deposition of lipofuscin-like material in retinal pigment epithelial cells, leading to photoreceptor damage and visual impairment. Additionally, it can cause cardiac conduction abnormalities, including prolongation of the QT interval, which increases the risk of torsades de pointes. The mechanism of toxicity involves the accumulation of chloroquine in the retina and heart, where it disrupts cellular function and leads to cell death.
**Why Each Wrong Option is Incorrect**
**Option A:** Chloroquine toxicity is known to cause retinal toxicity, which is a hallmark of its adverse effects. This option is incorrect because it is a recognized consequence of chloroquine use.
**Option B:** Chloroquine can cause cardiac toxicity, including QT interval prolongation, which increases the risk of arrhythmias. This option is incorrect because it is a well-documented side effect of chloroquine.
**Option C:** Chloroquine toxicity is not typically associated with hepatic toxicity. While chloroquine can cause liver function abnormalities, it is not a primary concern in the context of toxicity.
**Clinical Pearl / High-Yield Fact**
A key aspect of chloroquine toxicity is its delayed onset, which can occur weeks or even months after the initiation of therapy. This delayed onset makes it challenging to diagnose and can lead to misattribution of symptoms.
**Correct Answer: D. Chloroquine toxicity is not typically associated with hepatic toxicity.