THE EFFECT OF PROCESSING VARIABLES ON THE RELEASE OF IBUPROFEN AND CAFFEINE FROM CONTROLLED-RELEASE NONSWELLABLE CORE-IN-CUP COMPRESSED TABLETS

An aqueous soluble polymer such as hydroxypropyl methylcellulose (HPMC ), which is widely used in oral sustained-release drug delivery system s, swells when it comes into contact with an aqueous environment. In c ore-in-cup systems the swelling of the HPMC splits open the cup portio n of the tablet. This study investigated the use of acacia, tragacanth , polyethylene glycol 6000 (PEG 6000), and hydroxyethylcellulose (HEC) as possible alternatives to the use of HPMC to control the release of caffeine (soluble) and ibuprofen (insoluble) from core-in-cup compres sed tablets. It also investigated the possibility of producing a core- in-cup system that had the ability to release caffeine and ibuprofen f or a maximum time of constant release of 8-12 hr. A preliminary study revealed that acacia was most effective for the release of caffeine fr om the core-in-cup compressed tablets, and that PEG 6000 was most effe ctive for the release of ibuprofen from the core-in-cup compressed tab lets. On further investigation it was found that by means of adjusting the hardness of compression and the concentration of polymers used, i t was possible to formulate a core-in-cup system that could release dr ug at a constant rate from the core-in-cup compressed tablets for 8 to 12 hr.