According to the sources provided, it is not necessary to take Tylenol every day, and it is important to be cautious when taking it. Tylenol is a brand name for acetaminophen, which is an over-the-counter pain reliever and fever reducer. It is commonly used to treat mild to moderate pain and is available in different forms such as tablets, capsules, and liquid.

The first source [1] provides information about the patent status of Tylenol and its active ingredient acetaminophen. It does not provide any information about whether it is necessary to take Tylenol every day.

The second source [2] warns about the potential risks of taking too much Tylenol without knowing it. The article states that acetaminophen is safe when used as directed, but taking more than the recommended dose can cause liver damage and even death. The article recommends checking the labels of all medications that contain acetaminophen and avoiding taking more than the recommended dose.

The third source [3] provides information about the safety of acetaminophen. It states that acetaminophen is safe when used as directed, but it can cause liver damage if taken in high doses or for a long time. The article recommends being cautious when taking acetaminophen and following the recommended dose and duration of use.

In conclusion, it is not necessary to take Tylenol every day, and it is important to be cautious when taking it. Taking more than the recommended dose can cause liver damage and even death. It is recommended to check the labels of all medications that contain acetaminophen and follow the recommended dose and duration of use.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/TYLENOL
[2] https://www.goodrx.com/acetaminophen/are-you-taking-too-much-tylenol-without-knowing-it
[3] https://www.health.harvard.edu/pain/acetaminophen-safety-be-cautious-but-not-afraid