Question
Posted on: March 6 2013Next cream breaks: prednisolone 0.5 g erythromycin 2.4 g cold cream ad 100g
Composition Cold cream:
White wax 8gIs there an incompatibility between erythromycin and emulsify? What is the reason? We have the CR è me then made in CETOMACROGOLCR è me NF6, not buffered and everything is perfect.
walschot 10g
Peanut oil 52g
emulsify c83 5g
Aqua Conserv 20g
Castor oil 5g
Sorbic acid 0.2 g
Answer
Finding what is causing the breaking of the CR è me is not easy!!
an immediate incompatibility between erythromycin (Alcalisch) and sorbitanoleate, I doubt.
but a reaction of erythromycin with the free fatty acids, present in the walschot and the peanut oil, as well as sorbic acid for the formation of a salt is not excluded. These salts have presumably O/W Emulgatorische properties.
One can prepare the cool ointment without sorbic acid since we have to do here with a W/O cr è me and preservatives are much less necessary; In addition, there is already aqua Conservans.
Further, I would add 1.5 monostearine to reinforce the W/O emulsifiers.
to finish I have to point out that with the use of CETOMACROGOLCR è me you made a serious leap: from a fatty ointment to an O/W cr è me!
an immediate incompatibility between erythromycin (Alcalisch) and sorbitanoleate, I doubt.
but a reaction of erythromycin with the free fatty acids, present in the walschot and the peanut oil, as well as sorbic acid for the formation of a salt is not excluded. These salts have presumably O/W Emulgatorische properties.
One can prepare the cool ointment without sorbic acid since we have to do here with a W/O cr è me and preservatives are much less necessary; In addition, there is already aqua Conservans.
Further, I would add 1.5 monostearine to reinforce the W/O emulsifiers.
to finish I have to point out that with the use of CETOMACROGOLCR è me you made a serious leap: from a fatty ointment to an O/W cr è me!