Bloating, nausea or vomiting, and stomach pain are among common side effects associated with barium sulfate. People taking barium should check with a doctor right away if these effects appear, according to Drugs.com. Tightness in the chest, breathing problems and wheezing are also concerning side effects.
More severe side effects associated with barium include continuing constipation and cramping, according to Drugs.com. In some cases, physicians may advise patients that moderate side effects are normal during the first few days taking barium, but the effects should subside. Some people are also at risk of allergic reactions to barium or its interaction with other medications, reports Mayo Clinic. Doctors typically perform diagnostic testing to identify such issues.