Dihphenydramine works by blocking histamine H1 receptors. It does not prevent the actual release of histamine from mast cells, but prevents it binding to its receptors. This in turn prevents the release of other allergy chemicals and increased blood supply to the area, and provides relief from the typical symptoms of bites and stings. This cream is most effective when applied as soon as possible to the affected area of skin.

This cream also contains zinc oxide which helps to soothe the skin, and camphor which gives slight pain relief.