At Ann & Robert H. Lurie Children's Hospital of Chicago (Lurie Children's), the current practice is to prescribe children with oral Tylenol as needed every 4-6 hours post strabismus surgery. Prescribing Tylenol "as needed" leaves more room for error for parents to be under-dosing their children, which can lead to avoidable pain. This study aims to figure out if children ages 4-12 years old will feel significantly less pain and discomfort when given regimented Tylenol every 6 hours for 48 hours after strabismus surgery (eye muscle surgery) compared to controls whose parents are instructed to give Tylenol every 4-6 hours as needed for 48 hours after surgery. To date, there have been no studies comparing patient outcomes between those taking Tylenol regimen and those receiving Tylenol as needed after pediatric surgery.

Main hypothesis:

Children ages 4-12 years will feel significantly less pain and discomfort when given regimented Tylenol every 6 hours for 48 hours after strabismus surgery (surgery to correct misaligned eyes) compared to controls whose parents are instructed to give Tylenol every 4-6 hours as needed for 48 hours after surgery.

Primary Objective At Lurie Children's, the current standard practice is for patients to be prescribed oral acetaminophen as needed every 4-6 hours after strabismus surgery. However, making the acetaminophen "as needed" leaves room for error for parents to be underdosing their children and, thus, leads to increased pain felt by these pediatric patients. To date, there have been no studies comparing patient satisfaction outcomes between a group taking a course of scheduled acetaminophen every 6 hours and to a group instructed to take as needed. The investigators plan to study the differences between these two groups by using the Parent's Post-operative Pain Measure (PPPM) questionnaire to survey parents and the Faces Pain Scale-Revised to survey children at their post-operative appointment.

Inclusion Criteria:

• Children between 4-12 years old
• Children receiving single muscle, bilateral horizontal strabismus surgery (that is, children who are having only one horizontal eye muscle in each eye operated on) at Lurie Children's hospital in Chicago, IL
• ASA classification 1 or 2. Note: ASA is a physical status classification system (scale of 1-6) created by the American Society of Anesthesiologists to describe patients prior to surgery. ASA 1 or 2 means the patient is either healthy or has mild systemic disease prior to surgery.

Exclusion Criteria:

• ASA classification 3 or higher (patient has severe systemic disease or worse)
• Contraindication to toradol (anesthesia)
• Contraindication to acetaminophen
• Previous strabismus surgery