Is it possible to overdose on ex-lax?

Ex-lax overdose. Some of the most common potential side effects with Dulcolax are diarrhea, abdominal cramps/pain, indigestion, ^ gas, weakness, feeling dizzy, ^ thirst and nausea. The sxs could increase considerably if you take an over-dose.
Yes. It is possible to overdose on any medication. If you overdose on this particular one, you will definitely feel it.