EzeeLab lets you download patient contacts which you can use to run
your SMS campaigns. To send bulk SMS in India you need comply by TRAI
guidelines and need to follow a process. It could take a week or more
before you can complete the process and start sending SMS to your
contacts. There are many services providers which can help you with this
process and let you send bulk SMS, you can find them by searching for
"bulk sms service" on Google. Eg.
Textlocal
,
MSG91
and many others.