FORMULATION OF DIRECTLY COMPRESSED PHENYTOIN SODIUM ORALLY DISINTEGRATING TABLETS BY SIMPLEX LATTICE DESIGN USING AVICEL® PH 102 AND ERA-TAB® AS DILUENTS

Abstract

The orally disintegrating tablets (ODT) consisted of phenytoin sodium (PS), a poorly water-soluble drug, were prepared by direct compression. According to simplex lattice design; the various ratios of the two direct compressible diluents, microcrystalline cellulose (Avicel^® PH102) and spray-dried rice starch (Era-Tab^®) utilized in the tablet formulations were predetermined. Cross-linked polyvinylpyrrolidone (crospovidone, Polyplasdone^® XL) was used as disintegrant. Saccharin sodium, magnesium stearate and talcum were used as sweetening agent, lubricant and glidant, respectively. The prepared tablet formulations provided disintegration times between 4 to 107 seconds. The tablet formulation containing 1:0 Avicel^® PH 102:Era-Tab^® provided the fastest disintegration times of 4 seconds. From the obtained tablet disintegration times, the equation representing the relationship between disintegration time and the ratio of Avicel® PH 102 to Era-Tab^® was constructed. From this equation, the validated formulations containing 0.17:0.33, 0.33:0.67 and 0.67:0.33 Avicel® PH102:Era-Tab^® were prepared and tested for tablet disintegration. The tablet formulation yielded the observed and predicted disintegration times of 81, 51, 12 and 75, 51, 16 seconds, respectively. The tablet formulations containing 1:0 and 0.67:0.33 Avicel® PH 102:Era-Tab^® which exhibited the fastest disintegration times were tested for tablet dissolution. Their percentages of drug dissolution at the 30th minute time interval were 69% and 87%, respectively. The tablet formulation containing 0.67:0.33 Avicel® PH 102:Era-Tab^® met the USFDA disintegration time requirement for ODT and passed the USP criteria for prompt phenytoin sodium dissolution test.