Whether writing currency option is profitable?

I have seen that when it comes to expiry, the currency option contracts almost come to zero.So I would like to know that whether it is profitable to write options at the first of the month and buy at the time of expiry. Due to time value decay,the price should come down,right?Is there any risk in this , writing with 3-5 lakhs?

Hmm… there is no easy answer to this. Writing options is very similar to running an insurance business, you can keep making small amounts of money, but if you are not hedged properly there could be one big move against you that cleans you out. Suggest you to go through this options module: http://zerodha.com/varsity/module/option-theory/