All drugs, including the ibuprofen in Advil, have a lethal dose. It is estimated by the Royal College of Physicians that 400 milligrams per kilogram (a little over 180 milligrams per pound) of ibuprofen could kill a person. For an average man, it means about 150 Advil 200 mg tablets.
Even if not taken at a lethal dose, ibuprofen has several potentially dangerous side effects recognized by the FDA. Ibuprofen is known to cause severe liver damage if taken in high amounts. Also, according to the FDA, people who take ibuprofen regularly are at a higher risk of gastrointestinal bleeding. All non-steroidal anti-inflammatory drugs (NSAIDs) may put long-term users at risk from heart attack or stroke say the FDA.