Related Experiment Video
Updated: Oct 12, 2026
11:39
The Goeckerman Regimen for the Treatment of Moderate to Severe Psoriasis
Published on: July 11, 2013
[Lotion with hydroquione - tretinoin]
Journal De Pharmacie De Belgique
|September 18, 2014
Abstract:
The observed precipitation in a lotion containing 4% of hydrochinon and 0,03% of tretinoine is evaluated. To dissolve both actives, 10% propyleneglycol is used and the alcohol concentration varied. From the results it is demonstrated that at least 54 ml of ethanol 96 degrees is necessary to dissolve both actives. It is also demonstrated that the addition of 0.2% of vitamin C, as antioxidant, is necessary to avoid coloration of the lotion, as a function of time, due to the presence of hydrochinon.
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o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox property is crucial in...
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox property is crucial in...
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