Originally Posted by Nobbi
Creams are not essential for a 12 h flight. At least not a large tube. Whereas I understand that "medications" are better transported in carry-on than checked since the latter can get lost, creams are not that difficult to replace. As for pills, no problem to carry them on. The only liquid I can think of that's essential is insulin, unless you consider liquid asthma meds. But then you'd have to take your nebulizer too.
In addition to what others have said, if the person checks it and it is lost (I'm now a week without my case after a return flight where due to a hold issue, the airline couldn't carry anyone's bag - I'll be able to collect it tomorrow, a week to the day after I landed in the UK, and 9 days since I gave it into the care of the airline), then they have to be able to remember the exact formulation, active ingredients and strength/concentration. All they may remember is the brand name, which may not be available or easily recognisable in another country and not the finer details of what exactly it is they are using. And different countries have different rules on what may be bought OTC, what may be prescribed and what may not be permitted at all.
With all that in mind, I think your statement is a little bit optimistic/naive.