1. something that is to happen or has happened to a particular person or thing; lot or fortune. 2. the predetermined, usu. inevitable, course of events. 3. the power or agency that determines the course of events.
Alternating between ibuprofen and acetaminophen every 2 hours because you have to wait 4 hours for each of them to take a second dose of the same thing. So instead you take a dose of Acetaminophen now, then Ibuprofen in 2 hours and back to Acetaminophen 2 hours later as needed.
Avoid taking ibuprofen if you are taking aspirin to prevent stroke or heart attack. Ibuprofen can make aspirin less effective in protecting your heart and blood vessels. If you must use both medications, take the ibuprofen at least 8 hours before or 30 minutes after you take the aspirin (non-enteric coated form).