抄録
Plain tablets containing a model drug, sulfamethizole (SMZ), were coated with triolein (TO), trilaurin (TL) and ethylcellulose (EC). The biological behavior of the coated tablets (TOTL-Tab), which are pH independent and sensitive to pancreatic lipase, was investigated in humans. Results of the administration of the tablets with or without an antacid, under fasting and non-fasting conditions, and at 0.5 h before and 0.5 h after meals, were examined. A comparison of the in vivo behavior of SMZ after the administration of these tablets was done using the following data : the lag time of urinary excretion (Ulag), the total urinary recovery percentage (X∞u), and the mean residence time after Ulag (MRTaf). A typical pH-sensitive tablet coated by cellulose acetate phthalate (CAP-Tab) was used as a reference. For the administration of a CAP-Tab alone, the Ulag obtained under both the non-fasting and fasting condition was longer than that of the plain tablet. However, Ulag after the administration of a CAP-Tab with an antacid became considerably shorter. This lag time was about the same as that obtained from the plain tablet, regardless of food ingestion. The obtained CAP-Tab MRTaf and X∞u values were not significantly different in comparison to the plain tablets. Under the non-fasting condition, Ulag, MRTaf and X∞u of TOTL-Tab were not affected by the co-administration of an antacid, and these values were virtually the same as those obtained from a CAP-Tab without an antacid. The urinary excretion data obtained after the administration of TOTL-Tab alone under fasting was analogues to the non-fasting case. When TOTL-Tab was co-administered with an antacid under fasting, the MRTaf was the much longer than that of the plain tablet, and the X∞u was almost a half that of the plain tablet. These results suggest that TOTL-Tab is useful as an enteric release preparation sensitive to pancreatic lipase in humans, except when antacids are taken under a fasting condition.
