Blister package for inhalable medicament

2There is provided a blister form medicament pack comprising (a) a base sheet in which blisters are formed to define pockets therein for the containment of inhalable medicament; and (b) a lid sheet which is sealable to the base sheet except in the region of the blisters and mechanically peelable from the base sheet to enable release of said inhalable medicament. The base sheet and/or said lid sheet have a laminate structure comprising (a) a first layer of aluminum foil; and (b) a second layer of polymeric material of thickness from 10 to 60 micron, said polymeric material having a water vapor permeability of less than 0.6 g/(100 inches) (24 hours) (mil) at 25° C.