And if so, how would I go about the process of declaring them?
I'm travelling to Norway, by the way, but highly generalizable answers are also helpful.
The answer will depend significantly on what country you're traveling to. As you haven't listed that, this is just a general answer and may vary depending on the specifics.
In general, as long as the medications in question are legal to possess in the country you're traveling to, and as long as you are carrying documentation to show that you are allowed to posses the medications in your home country, then you are fine. Documentation could include a prescription for the specific medication you're carrying, a letter from your doctor, labels on the container with your name on them - or preferably multiple of these. This documentation should in the language of the country you're visiting, or if that's not possible then in English.
Most countries will limit you to carrying a "reasonable" quantity. Obviously what that entails depends on the specific circumstances, but if you're in a country for 3 days, and you bring a 3 month supply, that would probably not be considered a reasonable quantity.
Most countries do NOT require you to declare medications that fall into the above category, however always check the immigration/customs form you need to fill out to see if there are any questions regarding such medications, in which case you should obviously answer "yes". Of course, you can always be over-cautious and declare them to customs even if not required - although that will likely do little more than cause a delay.
Obviously if you are going to declare them, it is best to refer to them as "medications" and not "drugs", as that's likely to have negative connotations.
Again, this is a general answer that WILL vary from country to country.
As someone who has always travelled with a lot of prescription medication, I always declare it. This prevents any awkward questions (I once had some in my carry-on get searched in Bolivia and had to explain that it was prescription in broken Spanish), and surprisingly seems to get me through customs faster in some places :)
Without fail, when I've declared that I have "drugs" (that's the word on the form) and then just say "they're prescription, would you like to see them or my doctor's letter?" they've always just shrugged, shaken their head and directed me through to the exit.
Some countries by law require that all medicines are labelled with the pharmacy description (no putting tablets in old marmite bottles or something strange), and I always keep a copy of my prescriptions and a note from my doctor. It's never failed me, and I have some controlled items too.
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