A 15-year-old Irish Draft gelding presented to Cornell's Equine and Nemo Farm Animal Hospital for colic and a presumptive nephrosplenic entrapment. Initial diagnostics, including an abdominal ultrasound and rectal examination, confirmed the entrapment of the left large colon over the nephrosplenic ligament. Initial medical treatment with phenylephrine administration followed by twenty minutes of exercise was performed but was unsuccessful. He was managed with intravenous fluid therapy, a lidocaine continuous rate infusion, and pain medications overnight. Phenylephrine administration, lunging, and percutaneous trocharization of the left dorsal colon were performed the following day but were again unsuccessful. All surgical options were declined, and the patient was medically managed until discharge. Abdominal ultrasound continued to show a nephrosplenic entrapment throughout his two-day stay at the hospital. His prognosis at discharge was guarded for resolution of the entrapment. Follow-up with the owner several months following discharge confirmed the patient was alive and doing well.