Don't take any pills. You will lose weight just because you are having your period and the bloating from fluid build up will leave after your period.
The safe way to lose weight is eating healthy, drinking plenty of water, exercising and getting enough sleep. Pills are a temp. and when you stop using them, you gain back all the weight you lost. It is all about learning how to discipline yourself. Period time always puts weight on for just that week. Don't freak out. And don't gamble with pills..:)