According to the sources provided, it is generally safe to take Tylenol (acetaminophen) and Advil (ibuprofen) together, as long as they are taken at the recommended doses and not more frequently than the recommended intervals. However, it is important to note that both medications can cause liver and kidney damage if taken in excess or for prolonged periods of time [2].

Regarding the question of how long to wait between Tylenol and Advil doses, the sources do not provide a specific time frame. However, it is generally recommended to wait at least four hours between doses of Tylenol and six hours between doses of Advil [3]. It is important to follow the recommended dosage and timing instructions on the medication labels, and to consult with a healthcare provider if there are any concerns or questions about taking these medications together.

In conclusion, while it is generally safe to take Tylenol and Advil together, it is important to follow the recommended dosage and timing instructions, and to avoid taking these medications in excess or for prolonged periods of time. If there are any concerns or questions about taking these medications together, it is recommended to consult with a healthcare provider [2][3][1].

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/TYLENOL
[2] https://www.drugs.com/medical-answers/safe-ibuprofen-with-acetaminophen-2991821/
[3] https://www.aboutkidshealth.ca/article?contentid=3260&language=english