Salbutamol

Salbutamol "In the 1960s, an increase in asthma deaths in Britain coincided with the increase in sales of isoprenaline inhalers. The circumstantial evidence implicated the high-strength isoprenaline (known as isoprenaline-forte) used in the inhalers. There was also evidence that some patients had used it more frequently despite worsening asthma, although the exact cause of the deaths remains unknown."
http://pubs.acs.org/cen/coverstory/83/8325/8325salbutamol.html