Gastrointestinal side effects of Mounjaro: Mounjaro (tirzepatide) is known to cause gastrointestinal side effects such as nausea, vomiting, diarrhea, and abdominal pain due to its mechanism of action as a dual GIP and GLP-1 receptor agonist. The left hypogastrium location could be related to the stomach or small intestine, which are common areas affected by these medications.

Diverticulitis: Inflammation of a diverticulum in the colon, which can cause abdominal pain, typically in the left lower quadrant. Given the location of the pain in the left hypogastrium, diverticulitis is a plausible diagnosis, especially if the patient has a history of diverticulosis.
Constipation: Although Mounjaro can cause diarrhea, some patients might experience constipation, which can lead to abdominal pain. The pain location could be related to the rectosigmoid area.
Irritable Bowel Syndrome (IBS): IBS can cause abdominal pain, bloating, and changes in bowel habits. The left hypogastrium pain could be consistent with IBS, especially if the patient has other symptoms like bloating or altered bowel habits.

Appendicitis: Although the pain is in the left hypogastrium, which is not the typical location for appendicitis (usually right lower quadrant), it's crucial not to miss this diagnosis due to its potential for severe complications if not treated promptly. Atypical presentations can occur, especially in older adults or those with an anomalous appendix location.
Intestinal obstruction: This is a serious condition that requires immediate medical attention. Symptoms can include severe abdominal pain, vomiting, and constipation. The pain could initially be localized to one area, including the left hypogastrium, before becoming more generalized.
Inflammatory bowel disease (IBD) flare: Conditions like Crohn's disease or ulcerative colitis can cause abdominal pain, diarrhea, and other gastrointestinal symptoms. A flare could present with pain in the left hypogastrium, depending on the area of the bowel involved.

Intussusception: A condition where a part of the intestine slides into an adjacent part, potentially causing bowel obstruction. It's rare in adults but can cause severe abdominal pain and is a medical emergency.
Mesenteric ischemia: Reduced blood flow to the intestines can cause severe abdominal pain, which might initially be localized. This condition is more common in older adults and those with cardiovascular risk factors.
Ovarian torsion or other gynecological emergencies: In female patients, ovarian torsion or other gynecological conditions can cause severe abdominal pain that might be referred to the left hypogastrium. These conditions are emergencies and require prompt diagnosis and treatment.