Effective non-opioid analgesics are of particular interest in ambulatory surgery, as providers may be able to reduce pain while avoiding perioperative opioids that can delay same day discharge. The value of maintaining an efficient flow of patients from the perioperative area to discharge is an important metric for same day surgery centers, and an improvement in efficiency with IV acetaminophen could potentially offset the increased cost of the medication while providing a more pleasant surgical experience for patients. The goal of this study is to compare the efficacy of intraoperative IV administration vs. preoperative oral administration of acetaminophen on postoperative opioid utilization, patient-reported pain scores, opioid-related adverse effects, and time to recovery and discharge from the post-anesthesia care unit (PACU) after ambulatory lumbar discectomy.

Inclusion Criteria:

• Age greater than 18 years-old
• Weight greater than 50 kg body weight
• ASA physical status I-III
• English-speaking

Exclusion Criteria:

• Weight less than 50 kg
• Pregnancy or breast feeding
• revision surgery
• Contraindications to the administration of acetaminophen (e.g. allergy, liver failure, etc)
• Chronic pain conditions unrelated to back pain
• Opioid tolerance ( defined as taking greater than oxycodone 20 mg daily for a week during the past month).

Only those performing postoperative assessments and the participants will be blinded.