don't use it as the first medicine to treat diabetes, or if you have type 1 diabetes or diabetic ketoacidosis. don't take trulicity if you or your family have medullary thyroid cancer, you're allergic to trulicity, or have multiple endocrine neoplasia syndrome type 2. stop trulicity and call your doctor right away if you have symptoms of a serious allergic reaction, a lump or swelling in your neck or severe stomach pain. serious side effects may include pancreatitis. taking trulicity with a sulfonylurea or insulin increases your low blood sugar risk. common side effects include nausea, diarrhea, vomiting, abdominal pain, and decreased appetite. these can lead to dehydration, which may worsen kidney problems. to help lower my a1c i choose trulicity to activate my within. ask your doctor about once-weekly trulicity.