• YAKHAK HOEJI
• /
• v.31 no.5
• /
• pp.286-295
• /
• 1987

The relationship between in vitro release and in vivo bioavailability of acetaminophen from suppositories was investigated. Effect of glycyrrhizin on the drug release and rectal absorption in rats was also examined. Suppositories containing 25mg of acetaminophen were prepared with Wecobee FS (fatty base) or PEG (water-soluble base) bases. The release from the suppositories were determined with USP rotating basket dissolution apparatus and with the suppository release tester. The temperature of the dissolution medium was very critical for the dissolution of acetaminophen from Wecobee FS suppositories. The bioavailability of acetaminophen was calculated from the plasma concentration-time curve after rectal administration of the suppositories to the rats. There were no significant differences in AUC following rectal administration of Wecobee FS and PEG suppositories, but the release and absorption from the Wecobee FS suppositories were faster than those from PEG suppositories. The dissolution rate obtained by the suppository release tester was better correlated with in vivo absorption rate constant than that by the USP dissolution apparatus. It suggests that the partitioning between rectal fluid and suppository base is the rate-limiting step in the rectal absorption of acetaminophen from suppositories. Glycyrrhizin was found not to affect in vitro dissolution and rectal absorption of acetaminophen.

• Journal of Pharmaceutical Investigation
• /
• v.27 no.3
• /
• pp.189-198
• /
• 1997

The purpose of the present study was to investigate the effect of medium chain fatty acid salts, reported as enhancers in insulin nasal absorption, on the rectal absorption of insulin in rats. The serum glucose and remained insulin level in perfusate were measured after rectal recirculation of insulin with or without sod. laurate, sod. caprate and sod. caprylate in situ. The addition of sod. laurate or sod. caprate reduced serum glucose concentration considerably. Sod. caprate (1.0%) showed the greatest promoting effect on the decrement of serum glucose. Eudispert hv hydrogels containing insulin with medium chain fatty acid salts were, thereby, prepared and evaluated. The release rate of insulin from Eudispert hv hydrogels was reduced with an increase in the content of Eudispert hv, and was raised with increasing NaOH concentration. Ten percent Eudispert hv hydrogels were offered for the rectal administration of insulin. The addition of 1.0% sod. caprate reduced serum glucose concentration remarkably after rectal administration of 10% Eudispert hv hydrogels containing insulin. The level of glucose decrement was greater by 30% compared to subcutaneous administration of insulin solution. From the above findings, Eudispert hv hydrogels would be used as useful rectal delivery systems of insulin.

• Journal of Pharmaceutical Investigation
• /
• v.16 no.4
• /
• pp.148-151
• /
• 1986

This paper was designed to investigate the influence of different suppository bases on both the rectal absorption and dissolution rate of lithium carbonate, and to compare bioavailability from rectal administration with that from oral administration. The dissolution rates were in such order as PEG 4000, surfactant A (Witepsol 15+sodium lauryl sulfate), surfactant B (Witepsol 15+cholic acid), Witepsol 15 and cacao butter. Among various suppository bases, the blood level of lithium carbonate after rectal administration was increased in the following order: surfactant A>surfactant B>PEG 4000>Witepsol 15>cacao butter. When it comes to compare oral with rectal administration in AUC values, surfactants and PEG 4000 showed similar blood levels to oral administration, but lipophilic bases such as Witepsol 15 and cacao butter showed far lower blood level than oral administration. Peak time in oral administration was 2 hrs, but those in rectal administration using various suppository bases were $6{\sim}8$ hrs.

• Journal of Pharmaceutical Investigation
• /
• v.24 no.3
• /
• pp.145-153
• /
• 1994

Ibuprofen is an effective non-steroidal anti-inflammatory drug (NSAID), but it has several limitations in clinical application because of low solubility in water and gastrointestinal irritation. A water-soluble salt of ibuprofen, ibuprofen Iysinate, has been synthesized to overcome these shortcomings, and it was formulated as suppository for rectal administration. Witepsol and polyethylene glycols were employed as suppository bases for either ibuprofen or ibuprofen Iysinate, in order to compare the bioavailability in rabbits. The plasma concentrations of ibuprofen were assayed by HPLC after a rectal administration of ibuprofen and ibuprofen Iysinate, respectively. In addition to the comparison of two suppository bases, the other factors which affect on rectal absorption were also evaluated, especially in the point of not only particle size and shape of ibuprofen Iysinate but also effects of additives such as stearic acid, cetyl alcohol and capric acid. And pharmacokinetic parameters such as AUC, $C_{max}$, and $T_{max}$ were also compared. In conclusion, spray-dried ibuprofen Iysinate which was polyporous and spherical shape gave an increased absorption from the rectal formulations with Witepsol Hl5 and stearic acid.

• Journal of Pharmaceutical Investigation
• /
• v.12 no.3
• /
• pp.88-92
• /
• 1982

Insulin administration rectally with the liposome has the hypoglycemic effect in the rabbits. The reducton in blood sugar was maximum at about 60 minutes after administration and continued for 4 hrs. at low level in these experiments. No hypoglycemic effect was observed in control administrated rectally without liposome. Rectal absorption of insulin has been effected by addition of the bile salt, as the protective agent which prevented denaturation and the phastransition of insulin in liposome-encapsulation. As a matter of the fact, a significant hypoglycemic action was obtained when the insulin-liposome was given by rectal administration. The use of this agent to enhance insulin absorption offers the possibility of a new approach to rectal insulin therapy.

• Journal of Pharmaceutical Investigation
• /
• v.15 no.4
• /
• pp.231-245
• /
• 1985

• Journal of Pharmaceutical Investigation
• /
• v.21 no.2
• /
• pp.73-78
• /
• 1991

The influence of different suppository bases on the rectal absorption and the dissolution rate of propranolol was investigated. The bioavailability of propranolol in rectal suppository was determined by comparing the area under the concentration-time curves(AUC) for oral administration with rectal suppositories in rabbits. The dissolution $rates(D_{20min})$ were higher in such order as tween (TWE), witepsol H-15(WIT), polyethylene glycol(PEG) suppository. The maximum blood concentrations $(C_{max})$ were 803.9 ng/ml for TWE suppository, 770.2 ng/ml for WIT suppository, 281.2 ng/ml for PEG suppository and 177.1 ng/ml for oral administration. The relative bioavailabilities were 233.5% for TWE suppository, 218.1% for TWE suppository, 191.3% for PEG suppository. The correlation between $D_{20min}$ and AUC, the time for dissolution in 75% and $C_{max}$, the mean dissolution time and the mean residence time showed significant linear relationship respectively.

• Archives of Pharmacal Research
• /
• v.18 no.4
• /
• pp.219-223
• /
• 1995

Rectal absorption of opeprazole, a proton pump inhibitor, from suppositories was studied in rabbits. The suppositories were prepared by the conventional melting method with two types of bases, water-soluble polyethylene glycol (PEG) 4000 and oil-soluble Witepsol H15 bases, and administered intractally (ir) to rabbits at a dose of 10 mg omeprazole/kg. The plasma omeprazole concentration-time profiles of the two suppositories were compared with those following intravenous 9iv) administration of the same dose. There were no significant differences between the two suppositories in bioabailabilities and peak plasma concentrations $(C_{max})$. Bioavaiabilities and $C_{max}$ of PEG- and Witpsol suppositories were 30.3 and 33.9%, and 7.0 and $5.6\mug/ml$, resepectively. However, PEG suppository showed significantly (p<0.05) shorter time to reach peak plasma concentration $(T_{max})$ mean absorption time (MAT) and mean residence time in the plasma (MRT) than Witepsol suppository. The $T_{max}$ MRT nad MAT were 25.0, 83.0 and 38.5 min for PEG syppository, but were 90.0, 122.5 and 78.0 min for Wiepsol supposiotory, respectively. These differences between thw two suppositories could be explanined by the difference in the in vitro dissolution rates between the suppositories. The dissolution of omeprazole form PEG suppository was reportedly much faster than that from Witepsol suppository. It suggests that plasma profiles of omeprazole, especially $C_{max}$ MAT and MRT, could be controlled by modifying the in vitro dissolution rate of the drug from the suppositories. Above results suggest that rectal suppository is worth developing as an alternative dosage form of omeprazole to the conventional oral preparations which need sophisticated treatments, such as enterix coating, to prevent acid degradation of the drug in the stomach fluid.

• YAKHAK HOEJI
• /
• v.43 no.2
• /
• pp.150-159
• /
• 1999

Hollow type suppositories inserted polyvinyl alcohol (PVA) hydrogel capsule containing propranolol·HCI (PPH) were prepared using different bases, polyethylene glycol (PEG), Witepsol H-15 (WH-15) and Witepsol W-35 (WW-35) to improve the controlled release of PPH. The release of PPH from the hollow type suppository inserted PVA hydrogel capsule was retarded than that from PEG, WH-15, or WW-35 hollow type suppositories in rat rectal cavity. When the suppositories were administered to rats, the controlled release of PPH was proved by the plasma concentration-time-profiles of PPH. No significant difference (p〈0.05) among the three different hollow type suppositories was observed in terms of AUC and MRT of PPH. WH-15 hollow type suppository inserted 12% of PVA hydrogel capsule caused irritation to rat rectal mucosa. However, the WH-15 hollow type suppository inserted PVA hydrogel capsule caused no severe irritation on rectal mucosa. The application of the hollow type suppositories using PVA in sustained rectal delivery of drugs might be feasible.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.23 no.4
• /
• pp.499-509
• /
• 1999

This study was carried out to investigate the effects of wearing disposable diaper with the endothermic agent on thermoregulatory response of infant. Five healthy female infants aged about 5 months were taken as a subject of this experiment. Experimental diapers were six kinds of disposable diaper constructed of nonwoven tissue, fluff pulp, super absorbent polymer, back sheet film, leg elastic, and 0g urea(A) 1g urea(B) , 2g urea(C), 3g urea (D), 4g urea(E) 5g, urea(F) respectively. Urea(98% or over purity) was used as an endothermic agent. Experiment was proceeded while infants were sleeping at 27.5$\pm$0.5$^{\circ}C$, 50$\pm$5% R.H, 0.04m/sec. Each disposable diaper's properties was tested. During the experiment rectal temperature skin temperature of 9 areas temperature inside the disposable diapers were measured, the results were as follows : 1) There was not significant difference among the diapers in absorption capacity retention capacity and rewet(p=0.05). The absorption under load was showed to A, B,