I don't travel too often but when I do I like to make sure I have any medicated cream that I'm using and a moisturiser with me. The tub of moisturiser that I get on prescription is a huge 500g one so that is something I need to think about. Luckily I got sent some smaller sample tubes of a new moisturiser, so on recent travels I have just packed one or two of those instead. I am very lazy with moisturising so realistically I don't need too much 😉
Another consideration is that I can't use shampoo with sulfates in without having an incredibly itchy head, so I'm usually not able to use any shampoo that hotels provide. If I'm going away for long enough that I will need to wash my hair whilst away, I will decant my shampoo into tiny bottles. I couldn't find a suitable bottle in any shops the last time I traveled so I ended up putting my shampoo in an old mouthwash sample bottle !
If I am travelling abroad and taking any prescription creams (or any medication really) with me, I like to take a copy of my script just in case anyone asks questions or wants to see that it is actually prescribed to me. I think this is probably a bit of being overly prepared on my part but I'd rather be like that than have to worry about any issues on top of the stress of travelling! Also when on a plane it's so important to stay hydrated so I make sure I drink lots of water, and I also make sure I apply a moisturiser or an oil to my psoriasis if it's looking a bit dry or angry.