Product characteristics and pharmacokinetics of intranasal ipratropium bromide

The in vivo absorption potential of ipratropium bromide nasal spray was evaluated in studies involving healthy volunteers (0.03%, 0.06%, and 0.12% dosage strengths) and patients with perennial rhinitis (0.03% and 0.06%) and the common cold (0.06%). The dose used was two sprays per nostril, corresponding to a total dose of 84 micrograms, 168 micrograms, and 336 micrograms for the three dosage strengths. These studies indicate that 10% or less of active drug is absorbed systemically after nasal administration based on the amount of unchanged drug excreted in urine in a 24-hour interval. In most instances, the plasma drug concentrations were undetectable. In none of these studies did plasma ipratropium concentrations reach a level where systemic anticholinergic effects are known to occur.