I developed a 15% urea foot cream 10 days back. Its stable at 40 C 75% RH, and 50 C for now. However, there are crystals formed in the tube orifice.
Need help on resolving this issue.
Herbal extract (coconut oil based) 3% - Provided by client
Cetyl Palmitate 2.5%
Arlacel 165 3.5%
Cetyl alcohol 2.5%
DM Water Qs to 100
Carbopol 940 0.4%
Should I be adding something else to stabilise urea?