This study is testing if dextromethorphan, a common cough medicine, can help reduce pain after total knee replacement surgery. Researchers believe it might have pain-relieving effects. You could be eligible if you are at least 18 years old, planning to have total knee replacement surgery, and meet certain health criteria (ASA classes I-III). However, you cannot join if you have a BMI (Body Mass Index) of 35 or higher, a history of opioid abuse, or severe vomiting after past surgeries. The main goal is to see if dextromethorphan reduces the amount of opioid pain medication needed in the 24 hours after surgery. This study plans to include 160 participants, but its current status is unclear.

Study design

This is a randomized, placebo-controlled study involving 160 participants. You would be assigned by chance to receive either dextromethorphan or a placebo (an inactive substance).

What's involved

You would receive 60 mg of oral dextromethorphan (or placebo) before surgery, and then 30 mg at 8 and 16 hours after surgery.

Compensation

Not stated in the trial record.

Follow-up

Your opioid use will be measured for 24 hours after surgery.

AI-generated from the public study record. Only the study team can confirm whether you're eligible — confirm details with them before making decisions.