Paroxetine hydrochloride: polymorphs and solvatomorphs.

The polymorphic (crystal systems for which a substance can exist in structures defined by different unit cells, and where each of the forms has the same elemental composition) and solvatomorphic (systems where the crystal structures of the substance are defined by different unit cells, but where these unit cells differ in their elemental composition through the inclusion of one or molecules of solvent) landscape of paroxetine hydrochloride have been critically evaluated in order to learn how many authentic crystal forms have actually been discovered. After a survey of the patent and open literature, it was determined that paroxetine hydrochloride has been crystallized in four genuine nonsolvated polymorphic forms and in four fully characterized solvatomorphic forms.