Which is the most appropriate formulation for tretinoine?

Tretinoine is usually processed in a CR è me or gel base. The problem lies mainly in the very small amount (0.1%) Which should be divided homogeneously. Tretinoine is water insoluble but dissolves in ethanol and isopropanol. If a cream is prepared then it is recommended to dissolve the tretinoin in two ml ethanol and mix it with a small amount of cremebasis. This concentrate is then further diluted with the remaining amount of CR è me. The use of a gel based on Carbopol offers the advantage that the Tretinoin can be dissolved in the ointment base, if the alcohol concentration is kept sufficiently high. Alternatively, a solubilizer such as Cremophor RH 40 (1%) can also be invoked. Stability becomes more critical than when the drug is suspended. Adding an antioxydance is imperative. Used are butylhydroxytoluene (0.05 to 0.1%), Alfa Tocopherol (0.1%)

Two commercial preparations can serve as a model:

1. Tretinoine Kefrane Gel
2. Acid-Avit cr è me

This last product is no longer in the trade. The composition was as follows:
Tretinoine 0.05%, Glyceryl Monostearas, sorbitol opl, Cetylester wax, Perhydrosqualene, Butylhydroxyanisol, Na EDTA, Mg sulfate, benzoeic acid and water up to 100 g.