Azelaic acid
"I have had some luck with reducing pustules with a product available in Australia - Azclear. It is a 20% azaleic acid. I have had a little bit of peeling - it's quite strong so I use it spareingly. For those in the US it is only  $8.95 Aus dollars. Yes! It doesn't need a prescription and it is made by a well trusted company - I'm sure it's able to be purchased online and shipped overseas. Well worth a try - I can't believe it's so expensive in the US!"