Advil, also known as ibuprofen, is a nonsteroidal anti-inflammatory drug (NSAID) used to relieve pain and reduce fever. However, prolonged use of Advil can lead to the development of ulcers in the stomach and small intestine [2]. These ulcers can cause various symptoms such as abdominal pain, nausea, vomiting, and loss of appetite [2][3]. In severe cases, Advil-induced ulcers can cause internal bleeding and anemia, which can lead to fatigue, weakness, and shortness of breath [3]. Additionally, Advil can cause damage to the kidneys and liver, which can lead to symptoms such as dark urine, yellowing of the skin and eyes, and swelling in the legs and feet [2]. It is important to note that the risk of developing Advil-induced ulcers and other related symptoms increases with prolonged use, high dosage, and pre-existing medical conditions such as a history of ulcers, kidney or liver disease, or heart disease [2][3]. Therefore, it is crucial to follow the recommended dosage and duration of use and to consult a healthcare provider before taking Advil or any other medication [2][3].

Sources:
[2] MedlinePlus. (2021). Ibuprofen. Retrieved from https://medlineplus.gov/druginfo/meds/a682159.html
[3] National Center for Biotechnology Information. (2017). Gastrointestinal toxicity of nonsteroidal anti-inflammatory drugs. Retrieved from https://www.ncbi.nlm.nih.gov/books/NBK310269/