What is an “active” ingredient?

The term “active ingredient” or “active agent” causes a lot of confusion in skin care. This is primarily because an active ingredient in skin products is not exactly the same as an “active ingredient” in a pharmaceutical drug.

An active ingredient in a drug is the ingredient that causes a change in the function of the human body-in other words, the ingredient that is doing the job.

Similarly, an active ingredient or active agent in a skin care product, are those ingredients that cause physical changes in the skin.  The tricky part here is that most skin care ingredients cause physical changes in the appearance of skin and not necessarily physical changes and are therefore not regulated by the FDA.   If they are not regulated, then they are NOT listed under active ingredients.  Essentially only those ingredients that are considered “drugs” are listed as active ingredients-among the common ones are sunscreens, salicylic acid, benzoyl peroxide and hydroquinone.

If an ingredient is not listed under “active” then it is most likely listed under “other” or “inactive” ingredients. This is again confusing because an “inactive” ingredient does not mean it is not doing anything or serves no purpose, it simply means it is not considered a drug.  Furthermore, there are also many chemical variants of ingredients so depending upon the chemical makeup, an ingredient that is typically listed as an active, may be listed as an inactive.  A common example is retinol.  A product may claim that it contains retinol however it is not listed under active ingredients.  This is because it may be listed as one of many OTC forms of such as retinyl palmitate, reinylaldehyde or retinyl acetate.

In addition to actives, a skin care formula will also contain a variety of functional ingredients that are used to give the product a particular texture, help the way a product absorbs or spreads on the skin or helps preserve it.

Keep in mind that the majority of ingredients and terms used to describe ingredients are not regulated and may not be consistent.

Bottom line:

Just because an ingredient is not listed as an “active ingredient” does not mean it is not in the product.  Comparing “actives” in skin care products is not apples to apples.  Just because two products may both contain 2% salicylic acid, for example, does not mean they are the same.  One may be more hydrating, penetrate differently or not preserved well.  It is the product’s complete formulation that determines how effective it is.