elderly hams- when to start metacam?

[lovehamsters01]

Hi!
so around a year and a half ago I adopted 4 hamsters- one syrian, one Campbells, and 2 robos.
they were all around 6 months old then so they're all just about 2 now. they are my 1st hamsters and I really could use some advice on elderly hamster care.
firstly, when and how do you know if your hamster can benefit from metecam?
My syrian hamster, Daisy was always extremely vibrant, wild, and very sweet and loving but chock-full of energy. ever since she got a UTI a month ago (her 1st illness) she's really slowed down. she responded well to the medication but she just doesnt have her old energy and I know its a matter of months now. she's very up and down, sometimes acting very tired and old and sometimes going on her wheel. she's still eating, drinking, using the bathroom, etc., and she isnt losing weight or fur, but her fur is much whiter and her ears much darker then it used to be.
I can't tell if she's sometimes in pain or not, sometimes she keeps her ears back all day and I just recently found out that might be a sign of pain?
I'm also a bit concerned cuz she seems a bit swollen by her tail area so I'm worried that the UTI was really something bigger.
BUT when she went to the vet for the UTI the vet said that other than that, she's in perfect health so I really think it's all old age. so back to my question, should I put her on metecam? is it something that I'll just know when she needs it intuitively?
my dwarf hamsters are actually ageing really well. my only concern is my robo, Princess, who is acting completely normal, tons of energy as usual, eating, drinking, everything but her face just looks, how should I put this, wrinkly. her eyes are always half closed, and a littly bit sunken and her face just has a strange appearance. her sister does not have this issue. at first I assumed I just kept seeing her when she just woke up but this is just how she constantly looks.
The reason I really want to avoid a trip to the vet is a) she's acting completely normal and b) she's very nervous around humans, even more than your typical robo. the car ride alone would be a huge stressor and the vet wouldn't be able to even get a good look without sedating her first.
if anyone has any advice I would greatly appreciate it
thank you!

[souffle]

I wouldn't use metacam without vet advice, It can have side effects and it should be needed and not used without professional advice.
If she's acting pretty much normal it does sound like her age creeping up on her. If she is worrying you with health concerns then she may well need a further vet check.