I wrote in an earlier blog post about how well Certain Dri anti-perspirant worked for me. In fact, it was the only anti-perspirant that I’ve ever tried that actually worked. But how does it work, and is it safe to use?
Certain Dri is a water-based anti-perspirant that also contains aluminium chloride. When Certain Dri is applied, the aluminium chloride is drawn into the skin’s pores along with the water. When the aluminium and water is pulled into the skin, the pores begin to swell. This swelling causes the sweat ducts to close so that sweat can’t get out.
How long an aluminium-based anti-perspirant will work for depends on the amount of aluminium contained in the anti-perspirant. The higher the content of aluminium chloride, the longer the anti-perspirant works. In the case of Certain Dri, the amount of aluminium chloride is high enough that the sweat ducts close for days at a time. This means that you only need to apply Certain Dri about every other day or so, though Certain Dri says that it will work for up to three days.
The difference between Certain Dri and other anti-perspirants is the ingredients. Certain Dri uses aluminium chloride while many other over the counter anti-perspirants use aluminum zirconium trichlorohydrex GLY. The aluminium chloride molecules are smaller than aluminum zirconium trichlorohydrex GLY, allowing deeper penetration in the sweat glands, stopping sweating more effectively than the other anti-perspirants.
The image above demonstrates the difference between regular anti-perspirants (purple) and Certain Dri (green). As you can see, the molecules in Certain Dri penetrate deeper, forming a more effective plug to stop underarm perspiration. This is the secret to Certain Dri and the key to why it works so well.