Hypersensitivity to intravenous ondansetron: a case report.

Area of Science:

• Pharmacology
• Clinical Medicine
• Adverse Drug Reactions

Background:

• Ondansetron, a 5-hydroxytryptamine3 receptor antagonist, is commonly used for chemotherapy-induced nausea and vomiting.
• Unusual adverse drug reactions have been reported with ondansetron use.
• This paper details a case of hypersensitivity to a single intravenous ondansetron dose.

Purpose of the Study:

• To report a case of hypersensitivity reaction to ondansetron.
• To emphasize the importance of cautious ondansetron use in outpatient settings.
• To raise awareness of unusual adverse drug reactions associated with ondansetron.

Main Methods:

• A 19-year-old woman received a single intravenous dose of ondansetron (4 mg) for nausea and vomiting.
• The patient developed immediate urticaria, treated with dexamethasone and chlorpheniramine.
• Causality assessment using the Naranjo scale indicated a probable reaction to ondansetron (score 6).

Main Results:

• The patient experienced an immediate hypersensitivity reaction (urticaria) following intravenous ondansetron administration.
• The reaction resolved quickly with prompt medical intervention.
• The patient had no prior history of ondansetron exposure or allergies.

Conclusions:

• 5-hydroxytryptamine3 receptor antagonists can cause severe adverse reactions, including anaphylaxis.
• Off-label use of ondansetron, such as for gastritis, may increase risks.
• Physicians should exercise caution with ondansetron, particularly in outpatient settings, to minimize avoidable adverse drug reactions.