Even when using the same Head and Shoulder shampoo I use at home, I still end up getting itchy/flaky scalp after just a few weeks in Thailand. I have stayed long-term in Singapore and didn't have this issue, it's only in Thailand (I cant compare it against other countries, unfortunately). Is it something in the water? Should I wash my hair with bottled water!? I think climate is too similar to Singapore to suggest that is the reason. And it doesn't matter what time of the year, it always comes on after a couple of weeks!