- Has taken any of the following drugs within 4 hours or 5 elimination half-lives (whichever is greater) prior to dosing: aspirin, acetaminophen (paracetamol), nonsteroidal anti-inflammatory drugs (NSAIDs, COX-2 inhibitors), opioids, opioid combination drugs, sedative-hypnotics, muscle relaxants, and/or sedating antihistamines