Advil is a brand name for ibuprofen, a nonsteroidal anti-inflammatory drug (NSAID) that is used to treat pain, fever, and inflammation [1]. While Advil is generally considered safe and effective when used as directed, it can cause some side effects [2].

The most common side effects of Advil include upset stomach, heartburn, nausea, vomiting, headache, dizziness, and drowsiness [2]. These side effects are usually mild and go away on their own, but if they persist or become severe, you should contact your doctor.

In rare cases, Advil can cause more serious side effects, such as stomach ulcers, bleeding, and perforation, especially if taken for a long time or at high doses [2]. Other serious side effects include kidney damage, liver damage, high blood pressure, heart attack, and stroke [3]. These side effects are more likely to occur in people who have a history of stomach ulcers, bleeding disorders, kidney or liver disease, high blood pressure, heart disease, or stroke.

It is important to use Advil as directed and not to exceed the recommended dose or duration of use. If you experience any unusual symptoms while taking Advil, such as severe stomach pain, black or bloody stools, chest pain, shortness of breath, or weakness on one side of the body, you should seek medical attention immediately.

In conclusion, while Advil is generally safe and effective when used as directed, it can cause some side effects, including upset stomach, heartburn, nausea, vomiting, headache, dizziness, and drowsiness. Rare but serious side effects include stomach ulcers, bleeding, and perforation, kidney damage, liver damage, high blood pressure, heart attack, and stroke. It is important to use Advil as directed and to seek medical attention if you experience any unusual symptoms [1][2][3].

Sources:
[1] DrugPatentWatch. (n.d.). Advil. Retrieved from https://www.drugpatentwatch.com/p/tradename/ADVIL
[2] GoodRx. (2021). Advil Side Effects. Retrieved from https://www.goodrx.com/advil/advil-side-effects
[3] Mayo Clinic. (2021). Ibuprofen (Oral Route) Side Effects. Retrieved from https://www.mayoclinic.org/drugs-supplements/ibuprofen-oral-route/side-effects/drg-20070602?p=1