GHB (gamma-hydroxybutyrate) is produced naturally in the human body in very small amounts. When taken as a recreational drug, and especially when taken in combination with alcohol or other drugs, GHB can be extremely dangerous. GHB is a central nervous system depressant.
International flights always allow carry-on luggage, but each airline has its own restrictions as to quantity, size and weight. Some international carry-on policies restrict bag weights to 11 lbs. or less, while domestic flights rarely have a weight limit.
Passengers claiming exempted items must separate them from other carry-on liquids and declare the items to airport security at the X-ray screening point. Duty Free Items Passengers on nonstop international flights to and from the United States can take any size containers of duty free liquid on a plane.