Depending on what airlines you fly with, there are different regulations on carrying liquids and gels.
%%SNIPPET_CommentsList%%For American airlines, the TSA (Transportation Security Administration) reported a new regulation about the banned items taken on board on September 26, 2006.
The new rule announced that air travelers may carry liquids, gels and aerosols in the carry-on bag when going through security checkpoints. Air travelers must put all liquids, gels and aerosols in 3-ounce or smaller containers. Only one quart-size, zip-top, see-through plastic bag is allowed for each traveler.
If you need to take lager amount of liquids, gels and aerosols (toothpaste, shampoo, etc.), you must put them in your luggage and check them with your airline.
Certain liquids, gels, and aerosols more than 3 ounces are permitted in reasonable quantities provided they don't contain any suspicious items or activities. At the checkpoint you will have to declare it to the Security Officers.