Risk of thyroid C-cell tumors. Semaglutide and tirzepatide caused thyroid C-cell tumors in rodents. It is not known whether they do in people. Do not use them if you or your family have had medullary thyroid carcinoma (MTC), or if you have MEN 2.
Do not use if you have had a serious allergic reaction to either medicine, or if you are pregnant, planning a pregnancy, or breastfeeding. Tell your provider about any history of pancreatitis, gallbladder or kidney problems, diabetic retinopathy, depression, or blood-sugar-lowering medicines.
Side effects. Common: nausea, diarrhea, vomiting, constipation and stomach pain, mostly when starting or raising a dose. Serious: pancreatitis, gallbladder problems, low blood sugar, kidney problems, allergic reactions, vision changes, fast heartbeat and suicidal thoughts. Get help right away for severe stomach pain, an allergic reaction, or thoughts of self-harm.