They only things that I can think of that would help you lose your voice for an entire month would be some sort of damage to your larynx or vocal chords.
I hesitate to list what kind of substances or injuries might cause that kind of damage, as I'm not sure exactly what you're asking here...
Do you want to do something to lose your voice on purpose? That sounds like a terrible idea, why would you want to do that?
If you're trying to get out of a choir recital or looking for an excuse to leave a boy band you're contractually committed to, I'd suggest asking a question based around the real problem you're facing, and forget about losing your voice.
