If you are currently taking another laxative, a diuretic or a blood thinner, talk to your doctor before taking senna.
Talk to your doctor about the possible dangers of taking senna if you have ever had heart disease or a bowel disorder like Crohn's disease or ulcers. Talk to your doctor if you have stomach pain, nausea or vomiting.
If you are pregnant, talk to your doctor before taking senna. If you are breastfeeding and your baby develops diarrhea, stop taking senna, as senna can be transferred to a baby through breast milk.
Young children may get serious rashes from taking senna. Use extreme caution when giving senna to children.