Advil is a brand name for ibuprofen, which is a nonsteroidal anti-inflammatory drug (NSAID) used to treat pain, fever, and inflammation [1]. According to GoodRx, ibuprofen can cause nightmares and disturbing dreams as a rare side effect [2]. Healthline explains that vivid dreams or nightmares can occur as a result of a fever, which Advil is commonly used to treat [3]. However, there is no direct evidence linking Advil to vivid dreams or nightmares.

In summary, while ibuprofen (the active ingredient in Advil) can cause nightmares and disturbing dreams as a rare side effect, there is no direct evidence linking Advil to vivid dreams or nightmares. It is important to consult with a healthcare professional if you experience any unusual side effects while taking Advil or any other medication.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/ADVIL
[2] https://www.goodrx.com/drugs/side-effects/medications-that-cause-nightmares-and-disturbing-dreams
[3] https://www.healthline.com/health/fever-dream