Abstract

It is well established that the polymorphic state of a solid can modify physicochemical properties and suspension stability of drugs. However, not much attention has been paid towards crystal habit, the other seemingly trivial property of a crystalline solid. This study reveals that different habits of sulphamethoxazole belonging to the same polymorphic state can be obtained by varying the crystallization conditions, normally associated with preparation of different polymorphs. This implies that the same polymorphic form can exist in different habits. The selected habits were found to differ significantly with respect to shape parameters, bulk density and dissolution rate. The suspension formulations containing these habits exhibited significantly different physical stability than that formulated with the parent drug material. However, due to insignificant difference in ΔH1,value of the crystals and inherent nature to be rapidly absorbeds the Ka,Tmax and extent of free as well as acetylated sulphamethoxazole excreted were not significantly altered.