This phase II trial studies the effect of botulinum toxin (Botox) in preventing postoperative pancreatic fistula after distal pancreatectomy. Postoperative pancreatic fistula (POPF) is a known risk of distal pancreatic surgery, in which leakage of pancreatic digestive liquids causes internal swelling that can be painful (termed inflammation). A valve-like muscle, called the Sphincter of Oddi, opens and closes, controlling the flow of digestive liquids from the liver (bile) and pancreas (pancreatic juice) to the small intestine (duodenum). After surgery, the Sphincter of Oddi may act to block the flow of normal pancreatic secretions, causing secretions to leak into the abdomen resulting in POPF. Botox is a drug that can cause paralysis of muscles. Giving an injection of Botox into the sphincter of Oddi before distal pancreatic surgery may reduce leakage of digestive fluids and potential POPF.