Specific prescription medication for travel can be recommended by your specialist travel doctor or regular doctor. It may include sleeping tablets (for jetlag and time zone management), malaria tablets (if you are travelling to an area that is predisposed to malaria) and a broad spectrum antibiotic.
The airline bags that are provided when traveling (sometimes in business class and economy) are useful for packing these in.
Carry your drugs, especially prescription drugs with you in your carry-on luggage, especially on long distance flights.
You may need your medication on the flight and if your baggage gets lost, you will certainly need them. Interrupting a prescription course of drugs will only add to the stress of your travel (and may be harmful to your health).