Sulfamerazine sodium

The excretion velocity of sulfamerazine is very slow, caused by a high reabsortion rate in renal tubuli. An increased diuresis by i.p. administration of saline or p.o. load with water has no effect on the sulfamerazine excretion velocity. The enhanced diuresis is accompanied by a decrease of the urine pH-value and consequently by a decreased dissociation rate of sulfamerazine.

Suspensions of sulfamerazine (10%) containing 0.2% docusate sodium were deflocculated because of repulsion between the negatively charged particles. Flocculation was induced by salts or by xanthan gum, which is anionic, in the presence of salts at concentrations below those at which salt flocculation resulted. The amount of gum necessary to produce a flocculated system was lower the higher the concentration of salt present. Calcium chloride and magnesium chloride were considerably more effective in this regard than sodium chloride. Gum flocculation produced aggregates with fewer particles and weaker bonding forces than did salt flocculation. The sedimentation rate of the suspensions decreased 5 to 10 times for each 0.1% increase in the gum concentration.

Chitosan is a non-toxic, biocompatible, biodegradable natural cationic polymer known for its low imunogenicity, antimicrobial, antioxidant effects and wound-healing activity. To improve its therapeutic potential, new chitosan-sulfonamide derivatives have been designed to develop new wound dressing biomaterials. The structural, morphological and physico-chemical properties of synthesized chitosan derivatives were analyzed by FT-IR, (1)H NMR spectroscopy, scanning electron microscopy, swelling ability and porosity. Antimicrobial, in vivo testing and biodegradation behavior have been also performed. The chitosan derivative membranes showed improved swelling and biodegradation rate, which are important characteristics required for the wound healing process. The antimicrobial assay evidenced that chitosan-based sulfadiazine, sulfadimethoxine and sulfamethoxazole derivatives were the most active. The MTT assay showed that some of chitosan derivatives are nontoxic.

The renal excretion of sulfaclomide, sulfamerazine and sulfamethoxypyridazine is delayed by increased fluid application in rats. The simultaneous administration of sulfonamides and ammonium chloride or sodium hydrogen carbonate causes, respectively, retardation and acceleration of renal sulfonamide excretion which is consistent with the change in urinary pH value. The retarded renal sulfonamide excretion with increasing diuresis is explained by the ensuing change in the urinary pH value. For clinical uses, a speedy renal excretion of long-time sulfonamides by increased diuresis can be expected only if alkalization of the urine is achieved at the same time.