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Question

Posted on: September 6 2016

How do I work 8% urea in 100g Elocom lipophilic cream?

Urea 8% in 100g elocom lipophilic cream... So can not change ointment base since Mometasonefuroate is not to get as raw material... Thought to use elocom ointment, but similar composition as lipophilic cream, or stable in it? How do you solve this? I saw on Qualenica an addition of Aerosil, but how much best? And then it also changes the concentration of corticoid?

Answer

- The active ingredient is mometasonfuroate 1 mg/g.-The other ingredients are:

elocom 0.1% lipophilic Cream:

White Vaseline, white beeswax, hydrogenated phosphatidylcholine, Hexyleenglycol, titanium dioxide, aluminium octenylsuccinate starch, diluted phosphoric acid, purified Water.  

The pH of the water phase is slightly acidic for the stability of mometasonfumarate (ester). The denomination indicates a W/O cream and the emulsifier is lecithin. We do not know the amount of water in the cream but urea is very well soluble in water and is probably, if good mixing, soluble in the water phase of the cream. But the urea should be reduced to a very fine powder beforehand. Use electric coffee grinder if possible, strain off the fine and cook on the sieve   remains.  

A solution of urea can adversely affect the stability of a W/O cream and so it is not excluded that the W/O cream breaks. Therefore the mention of   possibly adding Aerosil. It is of course not possible to predict the amount needed to restore the cream. This should be tested under the addition of small quantities e.g. 500 mg.