Possible Interaction: Polymyxin B and Calcium Supplement

“Physiological concentrations of calcium in serum antagonize the activities of colistin, polymyxin B , and gentamicin against Pseudomonas aeruginosa.”

“Because calcium was found to be antagonistic in vitro to the activity of colistin and polymyxin B on Pseudomonas aeruginosa, the effects of calcium and serum on gentamicin and carbenicillin were also examined.”

“These results suggest that PMB exerts effects on the acrosomal exocytosis triggered by Ca2+ and A23187 in boar spermatozoa.”

“Insertion of the cationic amphiphiles dodecyltrimethylammonium bromide or polymyxin B sulfate into the SL had a profound inhibitory effect on the calcium leak.”

“However, polymyxin B at higher concentrations (10-100 microM) greatly reduced Ca2+ -evoked catecholamine secretion.”

“These agents also stimulated phosphate incorporation into lysine-rich histone, a substrate for protein kinase C. Addition of diacylglycerol, an activator of protein kinase C, further increased histone phosphorylation, whereas polymyxin B , an inhibitor of protein kinase C, blocked the stimulatory effect of calcium and phosphatidylserine.”

“Conversely, insertion of a cationic amphiphile Polymyxin B , dodecyltrimethylamine) displaces Ca and is negatively inotropic.”

“Concentrations of polymyxin B higher than 0.1 mM result in an initial displacement of calcium , followed by an irreversible and sustained period of enhanced net calcium uptake.”

“Efflux of calcium is slowed at the higher polymyxin B concentrations, whereas efflux of potassium is enhanced.”

“Second, polymyxin B (less than or equal to 0.1 mM) causes a reduction in net uptake of calcium , and slows the efflux of both calcium and potassium.”

“ Polymyxin B , a circular polypeptide, inhibits the ATPase activity and Ca 2 + transport of muscle microsomes accompanied by a large increase in fluorescence enhancement in the presence of ANS.”

“This report describes the case of a patient prescribed polymyxin B to treat a surgical wound infection, which led to significant increases in fractional excretion of calcium , magnesium, and potassium and subsequent persistent decreases in the levels of these ions, with serious consequences for the patient.”