"Write it down" is a suggestion you hear a lot this time of year, usually in regard to "New Year Resolutions".

"Write it down" is also suggested in an emergency situation.  Studies have shown that even short term stress can impact your memory.

Let's say that you have followed our previous suggestions and have recorded your pet's normal vitals. Good for you!  But now something is wrong.  Maybe her temperature is higher than normal. WRITE IT DOWN. Don't rely on your memory when you are explaining the situation to your veterinarian. Even a one degree difference in temperature might make a big difference.

It doesn’t really matter where you “write it down”.  Maybe you’ve copied the sheet from Knowing Your Pet’s Health and you carry it in your Pet First Aid kit.  “Write it down” there.  Maybe you’ve used the Pet Tech app to record ICE information.  “Write it down” there.

“Write it down” is also a good suggestion even if the vet visit is for a normal check-up.  Ahead of time, write down any questions that you have.  During the visit, write down anything that you want to remember about what your vet says.

Actually, these suggestions also good for a successful doctor visit for you.
 

(Tucker says "I'd write it down, if I had thumbs".)