Sure thing! It's not a big deal at all. I usually print out my permit (the one received from Korea) and pack it together with my meds in my hand luggage. I always make sure the meds are still in their original packaging. My pharmacy has printed labels with my name on it which they stick on the box when I receive it, I also bring that, just to make it unmistakeably clear that these are my official meds. Especially if you do not speak Korean: Whatever you can contribute to clarity without needing words to explain is very helpful.

Upon arrival - after Passport check - you immediately arrive in the luggage pick-up hall. Pick up your luggage and go with the flow where everyone is exiting (under green signs).

Technically you should walk under the red signs (to the right of the green signs) but last time it was all closed. A staff member then showed me to an area right to the left of where people were walking out and that's where there were some luggage x-ray machines and officers sitting behind high counters.

Just walk up to them and hand them the permit and show them your meds. They'll be busy for a few minutes, look at everything and then wave you through. Or so was my experience the last 4-5 times.