Linzess
"If you're taking samples currently, please read this. I have to love and hate this medicine.
Pros
It does what it says it does. It makes you go!
It doesn't give you full on diarrhea if you take it every few days. Just soft stools which is a great thing!
Cons
You cannot take this medication everyday no matter what the doctor tells you. Maybe it's my body or something but I can promise you, your body will soon reject the medication if taken everyday for more than 5 days. 
If continued in such a fashion, you will bloat, cramp and become MORE constipated than before. It will plug you up FOR REAL. It's not strong enough to make you go a lot the next day if you need it.Take a weak laxative with it. 
Still the best IBS/Constipation meds I've found."