In Twitter there is no option to send more then one Direct message (DM), By default , twitter has allow to send one message at a time. This means time wastage. But it is possible now with a Twitter tool called MultiDM. With this tool you can send direct messages (DM) to 12 different users at a time.

It’s very simple to use. Just enter the TweetGuru MultiDM twitter app page and login with your Twitter account. Then you can send DM (or private tweets) multiple users.

Try TweetGuru Multi DM here