Life-threatening adverse drug reaction to paclitaxel. Postmarketing surveillance.

The mechanism of action of hypersensitivity reactions from paclitaxel has not been fully understood. It has not even been defined if they are secondary to paclitaxel, its vehicle or the premedication. Postmarketing pharmacovigilance is predominantly based on spontaneous reporting. These reports albeit biased and incomplete serve to detect previously unrecognised adverse events. We report a life threatening adverse event related to paclitaxel without any evidence of histamine release. It consisted of a cardiac arrest probably secondary to bradiarrhythmia or branch block.