A gel formulation includes a gelling agent—carbomers, hydroxyethyl cellulose, and hydroxypropyl cellulose are the most widely used—and solubilizers. Depending on the excipients used, a gel can be transparent (most common), translucent, or opaque.

Gattefosse gel-preparation principle

The challenge when developing a gel is to keep the drug in a solubilized state and to identify the right gelling agent. Thus the selection of appropriate solubilizer is very important and must be compatible with the gelling agent.

Gattefosse range of use of solubilizers and gellingagents


Transcutol® P is compatible with all types of gelling agents and can be used at a very high concentration in the gel without altering its structure. Clear gels are obtained.

Labrasol® is compatible with all types of gelling agents. Depending on the concentration, clear or opaque gels are obtained.

Capryol™ PGMC produces an opaque gel when used at <6% with hydroxypropyl cellulose.  

 Gattefossé Nov 2015 Efficient skin delivery no compromise with Transcutol®Transcutol® P is widely used as solubilizer in gels with many drugs, including capsaicin, dapsone, diclofenac, estradiol, ibuprofen, ketoprofen, lidocaine, menthol, methyl salicylate, nimesulide, oxybutynin, piroxicam, and tetracaine HCl.

Find out more on Transcutol® P in our white paper.