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.
Ibuprofen (such as Motrin or Advil) 1  Adults: The initial dose is 400 mg. Follow-up doses are 200 mg to 400 mg every 4 hours as needed, up to a maximum of 4 doses in a 24-hour period.  Children: Check with your child's doctor if your child is less than 6 months old or less than 12 pounds.