Combining Penetration Enhancers in a Gel Formulation

You're asking if you can combine Ethoxydiglycol, Laurocapram (Water Soluble), and Reservoir-Tech in a water-based gel and if it would be wasteful.

Here's a breakdown of their functions:

• Ethoxydiglycol: Acts as a solvent and carrier to help ingredients penetrate the skin. It can also help dissolve certain substances in the formula.
• Laurocapram (Water Soluble): This is a potent penetration enhancer specifically for water-soluble ingredients, designed to help them absorb into the skin effectively.
• Reservoir-Tech: Unlike the others, this ingredient is not a direct carrier. It works by forming a film on the skin that helps retain active ingredients and release them gradually over time. This can help reduce irritation and provide a longer-lasting effect, especially for ingredients like AHAs.

While it's sometimes possible to combine different types of delivery enhancers, using all three of these together in one formula is generally not recommended and could be wasteful or even reduce effectiveness.

Here's why:

• The description for Laurocapram (Water Soluble) advises avoiding its use with other carriers (except 1,2-Hexanediol), as the overall effect may be reduced. Combining it with Ethoxydiglycol might lessen its intended penetration-enhancing power.
• Reservoir-Tech functions differently (sustained release vs. immediate penetration) and the description notes it cannot be combined with Laurocapram types for certain ingredients like AHA/BHA. While not explicitly forbidden for all actives, its mechanism is distinct, and combining it with strong penetration enhancers like Laurocapram might counteract its slow-release function or lead to unpredictable results.

Using multiple penetration enhancers doesn't necessarily lead to proportionally better results and can increase the risk of irritation.

Conclusion:

Instead of using all three, it is more effective and less wasteful to choose the ingredient(s) that best suit the specific active ingredients you are using and the desired outcome:

• If you need help dissolving an ingredient and moderate penetration enhancement, Ethoxydiglycol might be sufficient.
• If you need strong penetration enhancement for a water-soluble active, Laurocapram (Water Soluble) is a good choice, but it's best used alone or only with compatible ingredients like 1,2-Hexanediol.
• If you are using potentially irritating actives (like AHAs) or want a sustained, long-lasting effect, Reservoir-Tech would be the more appropriate choice.

Combining Ethoxydiglycol and Reservoir-Tech might be possible depending on the active ingredient, as their functions are different (solvent/initial penetration vs. sustained release), but combining Laurocapram (Water Soluble) with either of the others is generally not advised based on the product information provided.