Groove pancreatitis is a rare complication of chronic pancreatitis that can lead to severe manifestations, including gastric outlet obstruction. A 37-year-old man with a history of chronic alcohol use presented with recurrent epigastric pain radiating to the back, accompanied by nausea and vomiting. Imaging revealed features of chronic pancreatitis such as pancreatic calcifications, pseudocyst formation, and a mass-like lesion in the pancreatic head causing duodenal stenosis. Despite medical management and endoscopic interventions like biliary and duodenal stenting, the patient experienced persistent symptoms due to complications such as stent migration and failure to relieve the obstruction. Nutritional support became essential because of malnutrition from exocrine insufficiency and the inability to tolerate oral intake. Differentiating between groove pancreatitis and pancreatic carcinoma was challenging, as imaging and clinical features overlapped, and repeated fine-needle aspirations were non-diagnostic. Ultimately, due to near-complete duodenal obstruction unresponsive to endoscopic treatment, the patient underwent an open gastrojejunostomy. Postoperatively, he demonstrated significant improvement, with the resumption of oral intake and stabilization of his nutritional status. Management required a multidisciplinary approach, combining medical therapy, surgical intervention, nutritional support, and addressing alcohol dependence to prevent further pancreatic damage. Early recognition and appropriate treatment of groove pancreatitis and its complications are essential to improve outcomes and prevent disease progression.