Theophylline is one kind of drug often used for asthma therapy with narrow
therapeutic index (5-15 mg/L) and short half-life time (3-7 hours). To solve this
problem, theophylline is modified into sustained release dosage form, with floating
drug delivery system. This study aims to optimize and determine the optimum
concentration of HPMC E6LV and carbopol 940 as matrices to produce good
floating tablet, using Simplex Lattice Design (SLD) method. Tablet was made using
wet granulation method. The tests were done for physical properties of tablets,
floating characters, drug level of tablets, and dissolution profile of tablets. The data
were analyzed descriptively and optimized using Design Expert Trial ver 11.1.2.0
software, so the influence of two matrices could be known. The result of the study
shown that the combination of HPMC E6LV and carbopol 940 as floating polymer
could accelerate floating lag time, increased the duration of floating, and sustained
the speed of theophylline release from the dosage form. The optimum formula
composition gained from Design Expert software with Simplex Lattice Design
(SLD) method were HPMC E6LV 64,279 mg and carbopol 940 75,271 mg, with
desirability value 0,611.