Abstract: A pharmaceutical MR (modified release) multiparticulate dosage form such as a capsule (once-a-day MR Capsule) of Methylphenidate indicated for the treatment of children with attention deficit hyperactivity disorder (ADHD), capable of delivering a portion of the dose for rapid onset of action and the remainder of the dose in a controlled manner for about 12 hours, is composed of a multitude of multicoated particles made of two populations of drug layered beads, IR (immediate release) and ER (extended release) Beads. The IR beads preferably are made by layering an aqueous solution comprising a drug and a binder on to non-pareil sugar spheres and then applying a seal coat to the drug coated cores. The ER Beads are made by applying an extended release coating of a water insoluble dissolution rate controlling polymer such as ethylcellulose to IR Beads.

Abstract: An improvement in the process of coacervation of chlorpheniramine maleate is provided whereby a predetermined amount of chlorpheniramine maleate charged to the process is maintained in the microcapsules by pre-saturating the coacervation medium with chlorpheniramine maleate.