Certainly, bringing melatonin on a plane is allowed, but it\s advisable to verify the airline\s and destination country\s customs policies before traveling. Generally speaking, melatonin is not considered a banned item, and you should be able to pack it in either your checked or carry-on luggage. <br>However, it\s worth noting that rules regarding medicines and supplements may differ depending on the country, so it\s best to review the laws and regulations of your destination before departure.