Bronchospasm following intravenous injection of ionic and non-ionic low-osmolality contrast media.

Eighty patients were given either intravenous Hexabrix 320 or Niopam 300 for urography, and any bronchospastic effect was assessed by measurement of forced expiratory volume in 1 s (FEV1). No significant difference between pre- and post-injection FEV1 was shown with either contrast medium. Minor side-effects were comparable, the only significant difference between the two being the higher incidence of nausea and vomiting with Hexabrix 320.