Excipients for direct tabletting, granulation, capsules, sachet filling and inhalation
Lactose is a disaccharide of glucose and galactose obtained from the whey fraction of bovine milk. Depending on the temperatures used to crystallize and dry the lactose solution, it may be produced in either of two crystalline types: monohydrate or anhydrous.
In addition, the lactose disaccharide also has the ability to form two stable isomers known as alpha-lactose and beta-lactose. These two isomers differ in the orientation of the hydroxyl group in the glucose moiety. The monohydrate crystal in primarily the alpha-form, whereas the anhydrous crystal is primarily the beta-form (Zadow, 1984). At equilibrium in water at room temperature, both forms will be present as 62.3% beta-form and 37.7% alpha-form (Whittier, 1944).
Lactose as Pharmaceutical Excipient
Lactose clearly meets the criteria for an ideal excipient. It is chemically and physically inert to other excipients and active ingredients. Widely available worldwide, lactose is wellcharacterized, easy to store, cost-effective and has low lot-to-lot variability (Bolhius and Lerk, 1973; Brittain, 1993). It is also suitable for both wet granulation and direct compression methods of tablet production. Typically, the crystalline grades are used in wet granulation and the spray dried forms are sed in direct compression.Click here for product brochure