Formulation and In Vitro Release Studies of Emulgels Containing Shea Butter and Diclofenac Diethylamine

Shea butter is a raw material widely used in cosmetology. Its use in the pharmaceutical sector is becoming increasingly popular. As it’s commonly produced in Burkina Faso, it can help reduce medicine costs.  Several dermatological formulations (creams, body milks, ointments) have been developed in our laboratories in Burkina Faso. However, some active ingredients are not compatible with those bases due to their hydrophilic-lipophilic balance. The emulgel form can thus be a solution. Moreover, this type of dermatological base has not yet been reported in the literature on shea butter. The main objective of our study was to develop an emulgel based on shea butter, and diclofenac diethylamine was chosen as the active ingredient. Emulgel formulations were prepared with shea butter, carbomer 980, or arabic gum and diclofenac diethylamine. Physical quality control was performed against the Diclofenac Reference emulgel. The better emulgel formulations were tested for in vitro release of diclofenac diethylamine, compared with the Diclofenac Reference emulgel. The formulated emulgel was homogeneous, whitish in colour. The pH ranged from 6.53 to 6.71. The emulgel made with 0.5% carbomer 980 had a viscosity close to that of the Diclofenac Reference emulgel. Their diclofenac diethylamine content conformed to standards (99.47% and 100.55%). The release rate of these formulations after 6 hours ranged from 58.66% to 66.26%. The diclofenac reference emulgel had a lower rate of 44.02%. Locally produced shea butter can thus be used to formulate an emulgel incorporating diclofenac diethylamine as the active ingredient. Keywords: Diclofenac diethylamine, emulgel, shea butter, carbomer, arabic gum.