Buclizine crystal forms: First Structural Determinations, counter-ion stoichiometry, hydration, and physicochemical properties of pharmaceutical relevance.

Buclizine (BCZ) is a chiral synthetic piperazine derivative which has antihistaminic, anti-muscarinic and antiemetic properties, and has been reintroduced as an appetite stimulant, especially for pediatric patients. Structural information about this drug, as well as other buclizine crystalline forms (solvates, salts and co-crystals) including the BCZ free-base (BCZ-FB), is non-existent. Here, we present for the first time the crystal structure of the monohydrochloride monohydrate salt of BCZ (BCZHCl·HO), and of its anhydrous form, BCZHCl.

Pharmacokinetics and pharmacodynamics of glimepiride polymorphs.

Glimepiride (GLIM) is used as an oral antihyperglycemic agent for treatment of type 2 diabetes. The drug presents two polymorphic forms (GLIM form I and GLIM form II) described in the literature, and according to in vitro data, GLIM form II is about 3.5 times more soluble and releases 2 times the drug amount than GLIM form I in the physiological pH range.