Continuous Extrusion Using a Raker Perkins MP50 (Multipurpose) Extruder

The Baker Perkins MP50 mixer/extruder has been used to produce paracetamol extrudates with a high drug loading. The extrudate had a high incidence of defects (ie surface roughness and shark skinning). Addition of hydroxypropyl methyl cellulose to the basic formula (of paracetamol/avicel/lactose) improved extrudability but did not significantly influence extrudate quality. The mixer/extruder offers significant advantages by reducing the number of pieces of equipment required for extrudate manufacture, but further formulation work or equipment modification is required for the formulations examined to extrude satisfactorily.