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.
Duty-Free Items: Passengers traveling internationally into the United States with a connecting flight will be permitted to carry liquids in excess of 3.4 oz or 100 mL in their carry-on baggage, provided they were purchased in duty-free shops and placed in secure, tamper-evident bags (STEBs).