Phenylpropanolamine arrhythmia with

In the past decade there has been increased emphasis on drug safety, and more public visibility of safety problems. The volume of reports now exceeds 250 000 spontaneous reports per year, and adverse events have been highlighted in the medical sector and also in the media. In parallel, the FDA has focused more intently on this area in both NDA reviews and in the postmarketing period. This has accompanied withdrawals of a number of products, such as cisapride, phenylpropanolamine and terfenadine, and special scrutiny of products associated with particular adverse events, such as cardiac arrhythmias (torsades de Pointes ) and hepatic necrosis. The result has been an emphasis on the concept of risk management of a product. This concept, which is due to be described in forthcoming FDA recommendations, stresses the need to identify potential... 

There are anecdotal reports of fatal cardiac arrhythmia (ventricular fibrillation) with a combined phenylpropanolamine and thioridazine regimen. 

A 27-year-old schizophrenic woman who was taking thioridazine 100 mg daily and procyclidine 2.5 mg twice daily was found dead in bed 2 hours after taking a single capsule of Contac C (phenylpropanolamine 50 mg with chlorphenamine 4 mg). The principal cause of death was attributed to ventricular fibrillation. Just why this happened is not understood but it is suggested that it may have been due to the combined effects of the thioridazine (known to be cardiotoxic and to cause T-wave abnormalities) and the phenylpropanolamine (possibly able to cause ventricular arrhythmias). 

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