Question
Posted on: March 6 2013I have to prepare a syrup for the first time with prednisolondisodium phosphate (PDNa).
Why is phosphate and Na2EDTA added to this mixtuur (5mg/ml). The abbreviation "S" added to EDTA is not clear to me. < br/>
R/prednisolone na phosphas 0.74 g
dinatrii Phosphas dihydricus 0.10 g
Na Dihydrogenophosphas dihydricus 0.21 g
Na Edetas 2 Aqua (s) 0.10 G
sorbitol 70% non cristaisabile 25.80 g
Aroma Bananae naturale simile 0.10 g
AQUA Conservans AD 100ml (= 107.1 g)
Answer
PDNa is an ester and can therefore hydrolyze. At a pH of 7 to 8 this is minimal. Therefore, the pH of this beverage is set using a phosphate buffer. PDNa also dissects under the influence of metal ions. This is countered by the addition of Na2EDTA. An explanation for the "s" I did not. Maybe "soluble"? Published stability research showed that after 12 months the Gehale to PDNa has not dropped. In the context of a magistal preparation there is no need to exceed this deadline.