Question
Posted on: June 7 2019How to avoid the separation in a W/O cream with Nystatin and salicylic acid
Answer
The formula of Nystatin shows you the presence of an amino group, which is probably more basic as ZnO
We can thus get training of Nystatin salicylate. It would not surprise me that we have to do here with an O/W emulsifier.
I do not exclude that increasing the amount of W/O Emulgaor (up to 10 g) offers a solution. If not, either of the components will need to be removed. ZnO will also react with Nystatin, since Nystatin has an acidic function. But I suspect that Zn-Nystatin is a W/O emulsifier.
The occurrence of all these reactions makes me opt for a water-free ointment.