Can artificial sugars cause diareeha?

That could be anything.... talk to the doctor, see a nutritionist, or start out weaning what you feel is effecting you.

Certain ones can.

you're probably lactose in tolerant milk chocolate, whip cream frosting etc.

Yes - Splenda has been known to cause the runs in people.

Yes and brittle bones.

more likely 'artificial diarrhea'

Do you have an allergy or intolerance towards sugar?