According to the Mayo clinic, the causes of acne are: Overproduction of oil, irregular shedding of dead skin cells and buildup of bacteria. Here is an overview
The reason why I actually wanted to post to this might not be to answer your question directly, but I did want to point out something about the link that you provided. One of the listed ingredients is Mercurous chloride. According to this Material Safety Data Sheet mercurous chloride :
R22: Harmful if swallowed.
R36/37/38: Irritating to eyes, respiratory system and skin.
R50/53: Very Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment.
S13: Keep away from food, drink and animal feeding stuffs.
S24/25: Avoid contact with skin and eyes.
S46: If swallowed, seek medical advice immediately and show this container or label.
S60: This material and/or its container must be disposed of as hazardous waste.
S61: Avoid release to the environment. Refer to special instructions safety data sheet.
I know the dose makes the poison, but you may want to check into that before purchasing any. In the meantime, try some benzoyl peroxide or salycylic acid