[Study of oxytetracycline solubility in an aqueous medium]

Solubility of oxytetracycline dihydrate in aqueous media was studied. It was shown that solubility of the drug in bidistillate at a temperature of 20 degrees was 195 gamma/ml, which was much lower than the requirements of some pharmacopoeia with respect to the drug solubility. Dependence of oxytetracycline dihydrate solubility in the aqueous medium on the values of pH and temperature was found. Indigency of the procedure described in the literature for determination of antibiotic solubility according to the dry weight of the filtrate on addition of large excesses of the solid phase to the system was shown.