Sucralfat Chemische Eigenschaften,Einsatz,Produktion Methoden
Beschreibung
Sucralfate is a complex of the sulfuric acid ester of sucrose and aluminum hydroxide.
Secondary polymerization with aluminum hydroxide forms intermolecular bridges between
molecules of sulfate esters with aluminum. Limited dissociation of the complex occurs in
gastric acid, but these anionic sulfate esters form insoluble adherent complexes with the
proteinaceous exudate at the abraded surface of a crater of the ulcerated area in the
stomach. This physical complex protects the ulcer from the erosive action of pepsin and bile
salts. Sucralfate also stimulates synthesis and release of prostaglandins, bicarbonate, and
epidermal and fibroblast growth factors. Significant ulcer healing effects are noted in
placebo-controlled trials. Only small amounts of sucralfate are absorbed systemically. In renal
impairment, there is a risk of accumulation of absorbed aluminum from the drug. Sucralfate
reduces absorption of other drugs, including H2 antihistamines, quinolone antibiotics,
phenytoin, and perhaps, warfarin
Chemische Eigenschaften
White Powder
Verwenden
Sucralfate, an aluminum salt of sucrose octasulfate, is used as an antacid and antiulcer medication. Bis- and tris-platinum complexes of sucrose show promise as antitumor agents. Sucrose monoesters are used in some pharmaceutical preparations.
Indications
Sucralfate (Carafate) is an aluminum hydroxide–sulfated
sucrose complex that is only minimally absorbed
from the GI tract. After exposure to gastric acid, the
compound becomes negatively charged, creating a viscous
adherent complex. This complex is believed to inhibit
back-diffusion of H .Other effects are a direct reduction
in pepsin activity and a slight rise in tissue
prostaglandin levels. Stimulation of a cytoprotection
mechanism may therefore assist mucosal healing. The
drug has no acid-buffering capacity.
Allgemeine Beschreibung
Sucralfate, 3,4,5,6-tetra-(polyhydroxyaluminum)-α-D-glucopyranosyl sulfate-2,3,4,5-tetra-(polyhydroxyaluminum)-β-D-fructofuranoside sulfate (Carafate), isthe aluminum hydroxide complex of the octasulfate ester ofsucrose. It is practically insoluble in water and soluble instrong acids and bases. It has a pKa value between 0.43 and1.19.
Sucralfate is minimally absorbed from the GI tract by design,and thus exerts its antiulcer effect through local ratherthan systemic action. It has negligible acid-neutralizing orbuffering capacity in therapeutic doses. Although its mechanismof action has not been established, studies suggestthat sucralfate binds preferentially to the ulcer site to form aprotective barrier that prevents exposure of the lesion to acidand pepsin. In addition, it adsorbs pepsin and bile salts.Either would be very desirable modes of action.
The simultaneous administration of sucralfate may reducethe bioavailability of certain agents (e.g., tetracycline, phenytoin,digoxin, or cimetidine). It further recommends restorationof bioavailability by separating administration of theseagents from that of sucralfate by 2 hours. Presumably, sucralfatebinds these agents in the GI tract. The most frequentlyreported adverse reaction to sucralfate is constipation (2.2%).Antacids may be prescribed as needed but should not be takenwithin 0.5 hour before or after sucralfate.
Clinical Use
Sucralfate is frequently used for prophylaxis of
stress-induced gastritis in patients in intensive care
units. It has also been successfully used in small numbers
of patients as a suspension enema to treat radiation
proctitis.
Sucralfat Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte