Of course yes, certain types of eye drops would cause that. When you are dropping eyedrops into your eyes, it would pass through your nose and enter your mouth if you drop too much. And it seems that you drink the eye drops, franking speaking, the eye drops are a little bitter. Because of some types of eye drops is made by saline. However, certain tyes of eye drops without saline could cause diarrhea because a chemical contains in the eye drops that is called tetrahydrozoline make that happen. It could irritate the body's system when ingesting. When it counteracts with some medications, particularly blood/heart prescritpions, tetrahydrozoline raises blood pressure as well.