The absorption site of cyclosporin in the human gastrointestinal tract.

Abstract

1. An emulsion preparation of cyclosporin was administered locally to different parts of the small and large intestine by gavage: to the duodenum (opposite to the papilla of Vater), jejunum (150 cm distal to the teeth), ileum (300 cm distal to the teeth), and to the colon descendens (30 cm proximal to the anus). 2. The bioavailability of cyclosporin after these instillations was compared with that after oral administration of a hard gelatine capsule formulation. 3. Cyclosporin was found to be absorbed predominantly in the small intestine. This may have implications for dosage in patients with reduced absorptive surface area.

The Contribution of Pharmacological Agents in the History of Organ Transplantation

“…Absorption profiles have been suggested to be particularly important in predicting pharmacological activity. The first formulation of CyA, Sandimmun ® oral solution, used carrier oil as its base, which was emulsified by bile acid after oral administration and absorbed in the upper digestive tract [42]. Therefore, Sandimmun ® displayed considerable inter-and intrapatient variability, as its absorption was bile-dependent and affected by concomitant intake of food.…”

Reduced cyclosporine absorption preceded acute allograft rejection in a child with a liver transplant

“…[1][2][3] Absorption of the drug has also been correlated with small bowel length in pediatric liver transplant recipients. 4 Based on this evidence, liver transplant recipients in the first few weeks after transplantation may be a high-risk group for potential malabsorption of oral cyclosporine because of alterations in bile salt production and secretion.…”

Formulation and evaluation of Gastro-retentive drug delivery system using Fenugreek gum as novel matrixing agent

“…Gastro-retentive DDSs exhibiting controlled drug release are significantly important for drugs which are: Acting locally in the stomach (e.g. antibiotics against Helicobacter Pylori, antacids and misoprostol) [15][16][17][18][19].Absorbed incompletely due to a relatively narrow window of absorption in the GIT, such as cyclosporin, ciprofloxacin, furosemide, L-DOPA, p-aminobenzoic acid and riboflavin [3,[20][21][22][23][24][25].Unstable in the intestinal or colonic environment such as captopril [26] or exhibit low solubility at high pH values such as verapamil HCl, diazepam and chlordiazepoxide [27][28][29][30]. Polymers are principle excipient in pharmaceutical dosage forms especially with modified release.…”