Study Objectives: Based on anecdotal reports of formoterol aggregating in mailboxes in the summer in Arizona, we examined the effect of heat on formoterol as well as on drug delivery.
Design: Formoterol capsules in original blister packaging were heated to 40 to 70 degrees C (104 to 158 degrees F) for 3 h and at 70 degrees C (158 degrees F) for 15 to 180 min. Capsules were removed from packaging, and a vacuum setup was used to dispense the formoterol into a filter using the device provided by the manufacturer.