Drug General Information (ID: DDI83RI9XK)
Drug Name			Ondansetron		Drug Info		Norfloxacin		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Antiemetics				Antibiotics
Structure

Mechanism of Ondansetron-Norfloxacin Interaction (Severity Level: Moderate)
Increased risk of prolong QT interval Click to Show/Hide Mechanism Graph
Drug Name		Ondansetron				Norfloxacin
Mechanism		Prolong QT interval				Prolong QT interval
Key Mechanism Factor 1
		Factor Name		QT interval
		Factor Description		Long QT syndrome is a heart signaling disorder that can cause a fast, chaotic heartbeat (arrhythmia). Many people may not exhibit symptoms, and usually the condition is detected during routine medical tests. In others, the most common symptoms include: sudden fainting, palpitations, dizziness, seizures, sudden death.
Mechanism Description		Increased risk of prolong QT interval by the combination of Ondansetron and Norfloxacin

Recommended Action
Management		Although the risk of a serious interaction is probably low, caution is recommended if levofloxacin, norfloxacin, or ofloxacin is used in combination with other drugs that can prolong the QT interval. Since the magnitude of QTc prolongation increases with increasing plasma concentrations of the quinolone, recommended dosages and intravenous infusion rates should not be exceeded. Patients should be advised to seek prompt medical attention if they experience symptoms that could indicate the occurrence of torsade de pointes such as dizziness, lightheadedness, fainting, palpitation, irregular heart rhythm, shortness of breath, or syncope.

References
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