Question
Posted on: March 6 2013Problem with following preparation: Salicylic Acid 0.5 gram boric acid 1.5 gram erythromycin base 1 gram Vaseline AD 50 gram
Answer
I think there is a clear difference between the compounds with erythromycin included in the TMF and your preparation. You have an excipient in which erythromycin is insoluble. This also applies to boric acid and partially to salicylic acid. In a water-free lipophilic medium, acidity cannot be spoken. Since it is not common to combine a pure fat excipient with erythromycin it is difficult to make a prediction about the stability in this center. I don't understand well why the Doctor combines erythromycin with petroleum jelly.