You would need an international cell plan to not get socked with long distance. Also some ships have their own cell system so you will find a charge for minutes used by that provider--like an access charge. Walkie talkies may be the best bet--but a lot of people have them and I noticed someone would hear mom--a lot of women would respond, and it took a few secs to sort out whose kid was on. Only so many frequencies are available, you know?
Titanium is an inert, nonmagnetic, metal. It should not cause and alarm to go off. I worked at an orthopedic clinic and we did provide people with a wallet sized card indicating they had internal metal as a just in case. Your doctor should have something similar.
I traveled with medication and supplements not in their original bottles. Not a good idea--the drug sniffing dogs are trained to detect certain "green" preparations, and some of their noses are not discriminating between drugs and herbals for health. It did not become a problem, but did slow us down some in customs. Now everything is in original bottles in my carry-on.
I would never trust a prescription medication in a luggage that did not stay with me at all times until I personally deposit it in my room.
Also understand that this is not like a hotel--you will not have the option of ferrying your own luggage to your room, it will be parted from you for several hours before reappearing OUTSIDE your door. I second the idea posed above of NO valuables in the case.
RCCL Nordic Empress 1993
RCCL Nordic Prince 1994
RCCL Explorer 2003, 2005
RCCL Navigator, 2004, 2007
RCCL Mariner 2006
RCCL Liberty 2008
RCCL Adventure 2009
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