When flying, you should ideally pack Tylenol and other essential medications in your carry-on luggage rather than your checked bag. There are several critical reasons for this strategy. First, checked bags can be delayed, lost, or sent to the wrong destination, and you do not want to be without pain relief or fever reducers while navigating a foreign city or waiting for your luggage to arrive. Second, the cargo hold of an aircraft experiences significant temperature fluctuations which could, in rare cases, affect the stability of certain medications, whereas the cabin is climate-controlled. From a security perspective, the TSA does not require you to place solid tablet medications like Tylenol in a separate bin or a clear plastic bag; they can remain inside your regular bag during X-ray screening. If you are carrying liquid Tylenol, it is exempt from the standard 3.4-ounce (100ml) limit because it is considered a medically necessary liquid, though you must declare it to the officer at the start of the screening process. Keeping it in your personal item also ensures it is easily accessible if you develop a headache or ear pain due to cabin pressure changes during the flight.