Aggressive Antiperspirant

Why are antiperspirants that contain aluminum chloride as an astringent ingredient so aggressive to the skin?
Aluminum chloride itself is an aggressive chemical and high percentages over 20% are not allowed for deodorants or antiperspirants and it is a criminal offense to produce one.  If you would apply pure aluminum chloride to your skin, you would get bad skin irritations that can result in necrotic skin tissue.
 
Even in lower concentrations, aluminum chloride remains aggressive. In addition to its natural aggressiveness,  hydrochloric acid is released when aluminum chloride comes in to contact with water (the sweat on the skin) and it becomes even more aggressive. 
 

1. To produce aluminum chloride (AlCl3), you add solid aluminum (Al) to aqueous hydrochloric acid (HCl) and mix it together. The resulting products will be aluminum chloride in water with hydrogen:

2 Al +  6 HCL(aq)   -->   2 AlCl3 + 3 H2O + 3 H2

2. To obtain pure aluminum chloride in a powder form, you will simply heat up the previous solution until all of the water and hydrogen has evaporated:

 

AlCl3

 

3. Before the aluminum chloride can be used to make an antiperspirant, it must be mixed with an alcohol solution, which always contains water. The products of this reaction will be aluminum hydroxide, hydrochloric acid, and more alcohol. Hydrochloric acid is very acidic and alcohol can also irritate the skin:

 

2AlCl3 + C2H6O + 6H2O   -->   Al(OH)3 + 6 HCl + C2H6O

 

 

This is why the skin gets irritated a lot, even more so when you use an antiperspirant with alcohol. These irritations can result in slight itches or bad inflammations. This is mostly only a problem in the upper skin areas where the itch occurs.
 
With an antiperspirant cream for example, it is not the same. You can wipe off the excessive cream and this will stop the reaction on the top of the skin, since only so much of the cream can be absorbed. This is why you can apply a good antiperspirant cream even directly after shaving your armpits, without having this bad itching feeling caused in the upper skin areas after you wipe it off. Since less cream can be absorbed as compared to alcohol and, since any excess can easily be wiped off, there is less antiperspirant to react with your body’s sweat to produce more hydrochloric acid.
 
Even though antiperspirants are the cheapest option to treat sweat initially, finding the right antiperspirant can be a long process. It can cost an appreciable amount of money at first as well, depending on how many different type and brands of antiperspirant you have tried. The ideal antiperspirant will cause the least irritation while reducing sweat for long periods of time.
 
This trial can cost a lot of money and time, e.g. if you try 10 antiperspirants with an average cost of $18, you'll have spent $180 and from there you'll still have ongoing costs (depending on how long the antiperspirant lasts and how expensive it is). All in all, you will spend a lot of money over time, which you could've also invested in a professional iontophoresis machine. Iontophoresis is proven to be highly effective and its ability to reduce sweat can last much longer. Learn more about iontophoresis ...