APLAUD Trial (Antibiotics vs PLacebo for Acute Uncomplicated Diverticulitis)

The goal of this clinical trial is to determine whether antibiotics improve recovery from acute uncomplicated diverticulitis (AUD) in racially and ethnically diverse United States clinical practice. The main questions it seeks to answer are: * What is the feasibility for completing a subsequent definitive efficacy trial of antibiotics vs. placebo to treat AUD? * What are the needs for successful recruitment of racial and ethnic subgroups? * What are the effects of a placebo compared to antibiotics for AUD on a range of key patient-centric efficacy and safety endpoints? * How do such effects differ by race and ethnicity? Researchers will compare a placebo to antibiotics to see if AUD can be treated without using antibiotics. Participants will: * Take two antibiotics or a matching placebo every day for 10 days * Receive analgesia, gastric protection, diet modifications, and a follow-up * Submit daily photos of pills to the study team to verify adherence

Inclusion Criteria: * Patients presenting to the emergency department with left-sided uncomplicated diverticulitis * Radiologic score (moderate diverticulitis per Ambrosetti classification) * Age 18-90 * Access to a smartphone with internet access. Exclusion Criteria: * Complicated diverticulitis (abscess, free air, peritonitis)- severe diverticulitis by Ambrosetti classification * Diverticulitis other than left colon * Contraindication to use of study medication (ie advanced renal failure or allergy to all antibiotics used in the study) * Concurrent cancer diagnosis * Concurrent IBD Diagnosis * Any other disease process with life expectancy \< 6 months * Concurrent chronic pain diagnosis. * Women in pregnancy or breastfeeding * Antibiotic treatment for any reason in the last 3 weeks * Diagnosis of prior episode of acute diverticulitis in the past 3 months * Significant comorbidities: diabetes mellitus with organic involvement (retinopathy, angiopathy, nephropathy), emergency assistance for a cardiogenic event in the last 3 months (acute myocardial infarction, angina, heart failure), decompensation of chronic liver disease in the last 3 months (Child ≥ B) and end-stage renal disease. * Immunodepression: the absence, and immunodepression is the presence, of any of the following: active neoplastic disease, hematologic malignancy, human immunodeficiency virus long-term corticosteroid treatment, immunosuppressant therapy (20mg pred (or equivalent) for \>2 weeks), transplant, splenectomy and genetic immunodeficiency * Previous colectomy * Patients with dementia, memory disorders or other cognitive impairment that would impact their ability to provide informed consent or otherwise participate in the trial