The Advil website recommends that people take no more than six 200-milligram tablets within a 24-hour period. Drugs.com notes that 3200 milligrams is the maximum allowable adult dosage of Advil per day.
Taking too much Advil can cause bleeding or perforation in the digestive tract, particularly in older people, Drugs.com warns. Long-term use can also lead to heart attack or stroke. These conditions are serious and can be fatal, which is why Drugs.com recommends that people take the smallest possible dosage of Advil to alleviate symptoms. Anyone who takes Advil and experiences black, bloody or tarry stools or coughs up blood requires immediate medical attention, as these are possible indications of bleeding in the digestive tract.