Hi, Thanks for writing in. Rabeprazole EC is a medication often given for stomach related problems. Purpose of this medication is to decrease acid formation in the stomach and cause healing of any ulcers if present. This medicine should be taken on empty stomach in the morning 30 mins before brushing teeth and half and hour before meals if taken during the day. That way it will give best results. It is safe and does not usually cause side effects in patients taking it. Rarely, like any other medication ,it can cause headache, diarrhoea, rash, infection and flu-like syndrome and dizziness, fatigue, constipation, nausea and vomiting. Hope this helps