The FAA regulation on items that can be carried on a commercial United States airplane are very specific. These regulations are laid out in the FAA Regulations, a large compendium of regulations governing all aspects of the airline industry. The regulations are created and overseen by the Federal Aviation Administration. This governmental agency is a part of the United States Department of Transportation. FAA regulation on allowed items covers personal items passengers can carry on in their carryon bag. These items include, but are not limited to, liquids and gels in containers no larger than 3 ounces. Medications and medical equipment is trickier. Most medications and medical equipment can be carried on but must be checked at security. They will most likely have to undergo extra security measures. In you plan to carry on medications or medical equipment you should plan on extra time spent at the security checkpoint. If not, the extra time it takes to secure your items might cause you to miss your flight.