- Patients who are willing to discontinue all non-steroidal anti-inflammatory drugs (NSAIDs) or other analgesic medication taken for any condition, including their knee pain with the exception of acetaminophen, up to 1000 mg (2 tablets) four times a day (q.i.d.), as needed (p.r.n.) (maximum 8 tablets or 4 grams per day). These patients must be willing to use only acetaminophen as a rescue pain medication for the knee pain during the study period and refrain from even acetaminophen use 24 hours prior to any office visit. All other analgesic medications for any chronic condition must be stopped (see exceptions for acute treatment of transient flares of pain). Patients must also be willing to abstain from any intra-articular (i.a.) or peri-articular injections to the knee or surgery during the course of the trial, except for the assigned study product.