Keep them in your carry-on luggage.

Don't put them in your checked luggage. You never know if you will see that luggage again.

Plus, airport employees have access to our luggage and you never know if someone might steal your meds for whatever reason. Or compromise them. I sure wouldn't want to put something in my mouth after it had been out of my sight for a while.

Personally, I keep my meds in my handbag or computer bag that I carry with me rather than in the small piece of luggage that fits into the overhead compartment.

Why?

Because, ever since the airlines started charging for checked luggage, more people have been fitting everything they need for their trips into one carry-on piece that fits into the overhead compartment, and I've been on a couple of flights where there were so many that the overheads were full. The airline employees gave us valet tags as we entered the plane and took our overhead-sized luggage away.

I have sleep apnea and must sleep wearing a CPAP machine so I will breathe. I keep it with me, no matter what. There is no way that I would put such an expensive machine into checked luggage and risk it being lost or broken. Plus I don't want to wonder what might have happened to it sanitation-wise while an airport employee went through it.

Same with meds. Keep them with you and don't risk losing them.